The invention relates to a PMOS radiation dosimeter based on a silicon on insulator. The PMOS radiation dosimeter comprises a silicon on insulator that successively includes top silicon, a buried oxide layer, and bottom silicon. Besides, the PMOS radiation dosimeter also comprises: a positive gate oxide layer, which is arranged on the upper surface of the top silicon; a source region, which is arranged at one side of the top silicon; a drain region, which is arranged at the other side of the top silicon; a source region polycrystalline silicide layer, which is arranged on the upper surface of the source region, and a source electrode, which is arranged on the upper surface of the source region polycrystalline silicide layer; a first isolation oxide region, which is arranged at one side of the source region; a drain region polycrystalline silicide layer, which is arranged on the upper surface of the drain region, and a drain electrode, which is arranged on the upper surface of the drain region polycrystalline silicide layer; a second isolation oxide layer, which is arranged at one side of the drain region; and a back gate metal layer, which is arranged on the lower surface of the bottom silicon, and a back gate electrode, which is arranged on the lower surface of the back gate metal layer. According to the invention, a PMOS radiation dosimeter with high sensitivity is provided; the manufacturing process of the dosimeter is compatible with an SOI CMOS technology; and an integrated level can be effectively improved.