Percentage of foreign residents in Japan was 1.39% (National Institute of population and social security research, n.d.), Within 15 working types of visa in Japan (Ministry of Foreign Affairs of Japan, n.d.), the visa for highly skilled foreigners exists while no working visa for middle or low skilled foreigners (Immigration of Bureau of Japan, n.d.). Due to the strict controlled national policy (Menju, 2012), the percentage of immigrants population has been stagnant from 1.26% to 1.39% in a decade (National Institute of population and social security research, n.d.). Regarding this issue, Japan should promote immigration by relaxing the short-term visa for skilled workers and improving the treatment for low and medium-skilled workers which will benefit Japanese citizens, immigrants, and their acculturation. Promoting a more relaxed immigration policy sustains the Japanese economy in terms of social security system and labor market. The increase of foreign workers may help the alleviation of age support ratio (the number of workers necessary to support a 65 years old recipient in social security system). Currently, 39% of the total Japanese population are more than 65 years old, and the fertility rate in Japan declined from 3.65 in 1950 to 1.44 (Bureau Ministry of Internal Affairs and Communications, n.d., 2017). To maintain the old age support ratio of 4.77 in 1995, an average of 10 million immigrants per year would have been necessary from 1995 to 2050 (United Nations, n.d., a). In addition to that, immigration population increase may support labor shortage in labor intensive and manual industries. In healthcare industry, Japan urgents employment who can provide nursing care to the elderly due to the growth of aging (Morgan, 2001). In construction industry, labor shortage affects not only the workers aging, but also acute of reconstruction for March 11 earthquake as well as construction for 2020 Tokyo Olympic (Japan Construction Information Center Foundation, 2017, Ganelli, G. & Miake, N., 2010, and Relentless Tokyo 2020 schedule, labor shortages hitting builders hard., 2017). Those labor scarce problems might be solved by the expansion of immigrant influx. Immigrant will perform significant roles on Japanese economic. Despite the possible prospect of unemployment of Japanese residents according to the migrant influx, increasing the number of immigrants does not always lead to unemployment of nation-born workers as well as their wage decreasing. As empirical example, the U.K. showed that immigration had no statistically significant effect on the overall employment outcomes of domestic resident workers (Dustmann, Frattini and Preston, 2013, Reed and Latorre, 2009). In addition to no correlation between the increasing of immigrants and the unemployment of the nation-born residences, immigration has small impact on average wages (Dustmann, Frattini and Preston, 2013, Reed and Latorre, 2009). Rather, enhancement of the movement of immigrants may help the creation of more employment opportunities since they consume products and services (Wadsworth, Dhingra, Ottaviano, and Reenen, n.d.). During the period 1996 to 2004 in the U.S., 0.46% of immigrants created new businesses compared with 0.35% of native-born workers. Additionally, immigrant workers in the U.S possess a higher innovation rate than native workers, acquiring the patents as double as the nation-born residence does. Patents that immigrants innovated turn into marketable products and services, resulting in the creation of new jobs. Therefore, increasing immigrants may be a opportunity to prosper the labor market in the home country (Constant, 2014).Immigrants can gain the life-standard improvement, the benefit by remittance, and the new skill and knowledge. Immigration in Japan may guarantee the safety as well as the health knowledge. OECD (n.d.) reported 71% of people in Japan felt safe walking alone at night. Additionally, visiting and returning migrants may obtain health-improving practices such as drinking safe water and improved sanitation (World bank group, 2011). Regarding remittances (earnings that the emigrant workers send back) from Japan, immigrant home countries can benefit the improvement of households’ welfare (Chami, Barajas, Cosimano, Fullenkamp, Gapen, and Montiel, 2008), the reduction of the volatility of the economies by stabilizing overall demand for goods and services (Chami, R., Hakura, D. & Montiel, P., 2009), and the creation of a fiscal cushion for cash-strapped governments which can avoid debt crises (Chami and Barajas et al, 2008). In addition, immigrants can acquire new skills and knowledge such as vocational/technical skills, workplace organisation skills, culture and work ethics, and entrepreneurship skills (European Training Foundation, 2013). Transnational entrepreneurs of immigrants also can complement capacities of their adopted country and their country of origin, acting as a mediator (Bail, n.d.). In 2010, 2,274 Chinese managers and investors lived in metropolitan area for the benefits of the connection with international Chinese entrepreneur networks (Bail, n.d.). Immigrants will attain social and economic improvements.In spite of the concern of the arise of human rights violation of immigrants, the discrimination to immigrants can be reduced by reforming the government policy especially in the technical Intern Training Program (TITP). TITP was established in 1993, aiming to accepting foreign workers from developed countries and provide training in technical skills, technology, and knowledge (Ministry of Justice, 2017). Despite the purpose of TITP, immigrants are in reality discriminated within the program. For instance, under the contract of TITP, three Vietnamese workers continually being fired and rehired, losing their budgets as well as their unemployment insurances (Kamata, 2008). Not only that, Chinese immigrants with TITP visa suffered from overtime-working with undesirable compensation, being taken away their passports, and being forced to pay fines 2000 Japanese yen for forgetting to clean facilities such as bathroom after their using. (Fan, 2012). Regarding those problems, Japanese government ignores the plight of TITP immigrants (Kamata, 2008). Inspectors who oversee the TITP working conditions were occasionally reluctant to conduct investigations (Bureau of Democracy, Human Rights, and Labor, 2013). In order to secure the human right of immigrants, TITP requires to improve the treatment of immigrants urgently, which might enhance the increase of immigrants.Immigrants can promote acculturation between Japan and their home countries. In terms of the prosperity of Japanese culture in foreign countries, for instance, Chinese immigrant suggested selling traditional Nanbu cast-iron teapots of Iwate prefecture in China. Through his intermediation in the major contract with a famous tea house in Shanghai, Nanbu teapots obtained the popularity in China (Bail, n.d.). Immigrants can also transfer their cultures to host countries. From historical point of view, foreign-born migrants contributed to the creation of American musical tradition such as jazz (Hirschman, 2013). In addition, with the enhancement of the acculturation policy, cultural integration will be promoted by immigration acceptance. In Canada, for example, acculturation policy maintained cultural integration of immigrant (Phinney, Horenczyk, Liebkind, and Vedder, 2001). In case of Japan, Hamamatsu city in Shizuoka prefecture illustrates the beneficial cultural integration with immigrants. At present, 3.9% of total citizen are Brazilian (Yonekura, R. and Tani, M., 2011). In 2012, Hamamatsu city declared to embrace and promulgate multicultural diversity (Japan Foundation, 2012). Afterwards, with the expansion of ethnic business and community, local economy can strengthen co-ethnic networking between Japanese citizen and Brazilian immigrants which help reduce prejudice and discrimination. Additionally, by visiting the Brazilian store, Japanese residence recognized Brazilian as ‘open’, ‘bright’ ‘kind’, thus leading to cultural understanding and positive Japanese attitudes. (Ishikawa, 2015). Immigrants will enhance the cultural understanding. The increase of immigrants in Japan should be implemented, which will support the social security system and labor markets in Japan, improve the economic sustainability of immigrants and their homelands, and spur the cultural-understanding between Japanese and immigrants. As Japanese aging society issue worsen, the acceptance of immigrants will progressively be compelled to sustain Japanese economy. As the international network strengthen, cross-cultural communication with immigrants will help citizens understand the ethnic identities and cultures. With the promotion of influx of immigrants, Japan will succeed in the sustainable economic development and the improvement of Japanese reputation in international level.