Objective To analyse breeding and genetic stability in closed Colony of uncleaning Mongolian Gerbil (Meriones unguiculatus ) ． Methods Fourty pairs Mongolian Gerbil were selected randomly，recorded amount about reproduce and growth． Thirty three were selected for analysis genetic stability． Mitochondria D-Loop were amplified respectively by using PCR of a pair primers． The results from DNA sequencing were compared with the standard sequence of Mongolian Gerbil． Results The average 7． 01 Mongolian Gerbil were reproduced in one time． Male is higher than famale in body weight． The sequence of D-Loop gene was same in thirty three Mongolian Gerbil． Conclusion Polymorphism of mitochondrial DNA was not found． The Mongolian Gerbil colony showed good genetic stability．