The pump fields requirements for athermal laser amplifier and oscillator are described.The expressions of the pump fields are derived by use of rate equations. The pump distribution of an ytterbium-doped KY(WO4 )2 crystal is analyzed as an athermal lasers. For athermal laser amplifier, the pump intensity along the axis must be varied according to the laser intensity. With the increase of laser intensity, the pump intensity should be adjusted lower. For athermal laser oscillators, the pump distribution in the cavity is almost determined by the reflectivities of the rear and output coupler mirrors and gain media length. The pump intensity becomes lower and more close to uniform as the output coupler reflectivity is increased.