Abstract: Objective To study the expression of L-type calcium channel gene(α1c) and transient outward potassium channel gene (kv4.3 )during the procession of MSCs differentiating into cardiomyocytes. methods MSCs were isolated cultured,passaged, purified in vitro,and then exposed to 5-aza for 24 hours. we observed the morphology with microscopy. The expression ofα1C and kv4.3 gene was detected by Reverse transcription-polymerase chain reaction.Result:It displayed that MSCs had already expressed α1c and kv4.3.mRNA before 5-aza treatment. The expression of kv4.3 was significantly increased after 5-aza exposure at 24 hours ,4th day ,7th day,14th day,wheras the expression of α1C was impaired. Conlusion:L-type calcium channel and transient outward potassium channel played important roles during procession of MSCs differentiating into cardiomyocytes.