We assessed regional sustainable development by analyzing economic and environmental efficiencies. We applied material flow analysis (MFA) and data envelopment analysis (DEA) models to measure the material input and output for Liaoning, a province in northeast China. Liaoning is an old industrial area and has suffered from long-term excessive consumption of resources. This has taken its toll on the environment and has hindered its sustainable development. We analyzed the comprehensive evaluation of the environmental efficiency and the economic efficiency of Liaoning from 1990 to 2011 and the material flow in 2011. The material input quantity in 2011 was 965.19 million tons, and the local mining quantity was 705.04 million tons, accounting for a material input of 73%; the imported material quantity was 260.15 million tons. This accounts for a material input of 27% based on the MFA of Liaoning. From these results we conclude that the material consumption does not rely on imports, and the local resources meet the needs of economic and social development. The material output quantity is 132.33 million tons, and the material emission quantity is 31.19 million tons, accounting for a material output of 24%. The export total is 101.14 million tons, accounting for 76% of the total. From our analysis of the environmental efficiency of Liaoning from 1990 to 2010 based on the super efficiency Slacks Based Measure (SBM) model, we found that 2010 was the most effective year with the constant returns to scale, and the maximum efficiency was 1.13. 1991 was the year with the lowest efficiency (maximum 0.47, average 0.98). We conclude that the pure technical efficiency is higher than the comprehensive efficiency, and the scale efficiency restricts the comprehensive efficiency in the evaluation of environmental efficiency. Our analysis of the economic efficiency of Liaoning from 1990 to 2011 based on the super efficiency SBM model showed that the average value of the scale efficiency was 0.98, the average value of the pure technical efficiency was 0.97, and the comprehensive efficiency was 0.96. These values are different from the material flow and environmental efficiency values. This is because the pure technical efficiency restricts the comprehensive economic efficiency of Liaoning, and hence the scale efficiency is higher. From the perspective of input redundancy, the input redundant values of direct material input (DMI) and waste production from regional production processes (DPO) contributed significantly to the DEA model during years with efficiencies less than 1. The investment in fixed assets did not need to change, and the output variable of GDP and the proportion of the tertiary industries, such as service, financial and tourism industries, should have been improved in the years 1993-1996; this would have increased efficiencies to 1 or above. The employment population did not need to change, and the output variable of the proportion of the tertiary industries and Consumer Price Index (CPI) should have been improved in years 2004-2007, 2009, and 2010. These results indicate that the economic level of Liaoning has greatly improved; however, this has been to the detriment of the environment. The growth in secondary industries will result in the consumption of more resources and higher pollution levels. This has to be reduced by promoting tertiary industries, which are less energy dependent and rely on man power; the balance can be readdressed and the quality of the residents' lives will be improved.