The social security system of Macao has two components：social assistance and social insurance. The former was built a long time ago and is mainly to help poor people，and the latter is for mutual help，although its welfare characteristic is very strong since the government bears a heavy load. In order to make the system work better，social insurance must be reformed to balance the rights and duties of the public. Meanwhile，with the aging of the population，in order to meet the needs of quality life after retirement，a kind of provident fund is being introduced. This paper attempts to probe into the problems of the social security system in Macao，and see how the system can be reformed. We expect to establish a multi-level social security system of social assistance，social insurance，and a provident fund.