A living cell transplanting device (1) has a flexible tube (2) capable of accommodating living cells (12) and a cell pushing shaft (3) inserted into the tube (2). The tube (2) has a lumen (24) penetrating therethrough and a reduced diameter front end open portion (23). The shaft (3) has a small diameter end portion (32) having a diameter smaller than that of the reduced diameter front end open portion (23) and an enlarged diameter portion (33) having an outer diameter larger than an inner diameter of reduced diameter front end open portion (23). Owing to contact between the enlarged diameter portion (33) of the shaft (3) and the reduced diameter front end open portion (23) of the tube (2), a progress of the shaft (3) is regulated. By pushing the shaft (3) into the tube (2) after the contact between the enlarged diameter portion (33) and the reduced diameter front end open portion (23) finishes, the enlarged diameter portion (33) passes through the reduced diameter front end open portion (23) with expanding the reduced diameter front end open portion of the tube (2) and projects beyond the reduced diameter front end open portion (23) of the tube (2).