The RSSI circuit of the present invention includes: an IF amplifier section, which includes multiple stages of serially connected differential amplifiers for amplifying, with use of a current source IA provided as a power source for amplification, an IF signal corresponding to a received signal; an RSSI amplifier section for converting into current a voltage amplitude of an absolute value signal outputted from the differential amplifiers of the IF amplifier section, using a current source IB provided as a power source for conversion, and adding and outputting the converted current; and a current voltage conversion circuit for converting into voltage the output current from the RSSI amplifier section, and outputting the converted voltage as a measurement voltage value. The RSSI amplifier section is set so that a current value of the RSSI amplifier section is inversely proportional to absolute temperature. With the configuration, it is possible to realize an RSSI circuit, a received signal strength detection circuit and a wireless receiver, which are able to stabilize a strength measurement of a received signal relative to a change in temperature and to increase communication characteristics.