ethods for determining the dose distribution around a beta applicator are described.Experimentally a TLD dosimeter（about 10μm in thickness） was used to measure the dose and its distribution in a polystyrene phantom.Theoretically Berger’s method was adopted to calculate the dose distribution.An extrapolation ionization chamber was used to check feasibility of the above methods.It was found that the TLD method was in considerable agreement with the chamber method while the calculation was correct in a distance of 2-5mm to the source with an error of less than ±5%.