A new type detector was presented in this paper, which was developed based on novel sensors and new measuring circuits to achieve good sensitivity and reliability for HPM power measurement. Com pared with the previously developed X-band HPM detector, the new X-band detect or is characterized by 10 times higher sensitivity and over 9V output signal voltage amplitude at HPM power of 60kW. An S-band HPM detector was developed successfully for the first time. Both detectors can be used for power measuring of HP M whose pulse duration ranges from 10ns to 500ns.