The examination of the supply and demand for ecosystem services provides precise and fundamental scientific data for ecosystem management. Based on land use, remote sensing, meteorological and socio-economic data, we used the ecological process methods and models such as remote sensing retrieval, water balance equation, revised universal soil loss equation (RUSLE) and CASA to evaluate the grain supply (GS), water yield (WY), carbon sequestration and oxygen release (CS) and soil conservation (SC), and used the relevant socio-economic indicators to calculate the amount of key ecosystem services demand in the Pearl River Delta urban agglomerations from 1990 to 2015. We analyzed the balance between ecosystem services supply and demand at the grid, county and city levels. The results showed that:(1) Except for GS, the WY, CS and SC showed an increasing trend with fluctuation, increased about 52.2%, 21.8% and 73.4%, respectively. Ecosystem service supply was characterized by low levels in the central plain and high levels in the low mountain and hilly areas. (2) In addition to SC, the demand for GS, WY and CS had a trend of continuous increase, increased about 10.1%, 17.5% and 769.4%, respectively. The demand is high in the central plain areas and low in the low mountains and hills. (3) Except for SC and WY, the supply-demand index of the GS, CS and the integrated services declined at different level. In 2015, the supply-demand indices of GS and CS were -0.47 and -0.71, respectively. The study's findings would provide basic scientific information for decision-makers to grasp the balance and matching conditions between ecosystem service supply and demand, which could directly serve and guide regional ecosystem management and planning, as well as promote the sustainable development of eco-socio-economic system.