Regional Carrying Capacity (RCC)means the population and corresponding economic and social activities that the regional resources and environmenta
l capacity could carry ,within a confined temporospatial limits and under the condition of ensuring rational exploitation of resources and without deteriorating the environment. Being an important symbol to weigh the Regional Sustainable Development, the Regional Carrying Capacity  evolved from resource carrying capacity and environmental carrying capacity. Based on the summing-up of the research on carrying capacity of land ,water and key mineral resources at home and abroad and the research methods of environmental carrying capacity and regional carrying capacity, this paper puts forward a basic method of state space to measure the regional carrying capacity. It is the incomplete anastomose and existent divagation between practical regional carrying status and ideal regional carrying capacity in state space that induce three states of over-loading, full-loading and proper-loading. The authors put forward a method to describe quantitatively the regional carrying status and formula of computing the ideal states of regional carrying capacity sometime. This paper constructs RCC indicator system which includes the pressure index, support index and inter-region communication index and uses the weigh distribution method of entropy value .Based on the above-mentioned research, the paper evaluates quantitatively the regional carrying capacity, predicts and simulates the development tendency of the Regional Carrying Capacity and the Regional Carrying States the region surrounding Bahai Bay by the agency of System Dynamics.