Abstract: This work has measured the dose distribution of n, γ radiation field aroundthe building of the swimming--pool reactor by use of the highly sensitive neutronRem counter and PTB--H 7907 exposure ratemeter. The measured data show thatthe maximum value of n, γ dose are 3--4 times greater than the background oncertain distance from the building. Generally, the neutron doses are 2--3 timeslarge than γ doses on most points.