‘The Seoul Youth Activity Support’ which is launched 2016 is a very unique cash transfer program supporting youth transition to employment. It is consist of both a monetary support of KRW 500,000 monthly up to six months(Youth Allowance) and non-monetary service programs such as job support, training, consultation and community building. This study aims to evaluate the causal policy impact of Youth Activity Support Program 2020 on Youth well-being. Using difference-in-difference estimation, we analyzed panel survey data from a treatment group consisting of 11,831 Youth Allowance participants and control group consisting of 995 non-beneficiaries. This study identifies the significant treatment effects of the Youth Allowance on earned income and average hourly pay. Overall, the program participants have more actively participated in the labor market than the control group and it turned out that the financial support help to reduce deficiency among Youth. 31% of the treatment group was participated at least one of the non-monetary service programs. Among them, psychological consultation program had statistically significant positive impacts on reducing depression score among high-risk individual.