Provided are an antenna connection unit, a receiving device, a received strength correction apparatus, a capsule endoscope system, a correction method and a program that can prevent fluctuation in gain generated between individuals of a received electric field strength detection circuit. The antenna connection unit includes: a received electric field strength detection circuit 64 configured to detect received strength of a wireless signal according to a plurality of pieces of input power from a first receiving antenna 41 to an eighth receiving antenna 48 a correction parameter generation unit 683 configured to generate a received strength correction parameter for correcting the received electric field strength detection circuit 64 based on the plurality of pieces of input power and the received strength corresponding to each input power and a received strength correction parameter storage unit 661 for storing the received strength correction parameter generated by the correction parameter generation unit 683.