Abstract: The original Data Envelopment Analysis (DEA) models regard the DMUs as black boxes,that is,ignore the internal process for each DMU,which surely overrates the efficiency scores of DMUs.This paper advances a DEA-based efficiency-measuring model for two-stage production systems with constrained resources.The approach considers the internal process and its impact on the total performance.In reality the model is a special network DEA model,but differs from the previous network DEA models.The ap proach is helpful to offer information for managers to determine the inefficient originations and improve ment directions.The demonstration study approves the rationality of our approach.

Key words: Data Envelopment Analysis, efficiency evaluation, two-stage production system