We have proposed a novel use of pulsating living cells as a driving source for a micro bio-actuator. Cardiyomyocytes contract autonomously using chemical energy. But, contractile force of a single cardiomyocyte is not enough to actuate a micro robot or a mechanical system. So it is necessary to reconstruct cardiomyocytes to increase the ability to contract. We focused on the reconstruction of cardiomyocytes using a basement membrane protein mixture. In this paper, we fabricated a prototype cardiomyocyte gel structure. We confirmed that the ring-shaped cardiomyocyte gel structure condensed around the central cylinder within the PDMS mold and contracted synchronously and autonomously.