An electronic still camera which is able to substantially lessen the amount of trouble of inserting and drawing a PC card during photographing or when image data are transferred to a host computer such as a laptop computer, and which is able to increase the number of photographing. The electronic still camera has the PC card which is inserted into or drawn out from a camera body, which has the same shape as the PC card. The PC card or the camera body shaped like the PC card is inserted into a PC card slot of the host computer to transmit and receive the image data, etc. A camera casing including a taking lens, etc. is mounted in the camera body shaped like the PC card, and a sheet-like battery is provided in the camera body. The taking lens is capable of projecting from and retracting into the camera body.