The response of several large area (2 cm2), totally depleted surface-barrier and partially depleted, diffused-junction silicon detectors to beta particles has been investigated in the temperature interval of 300 to 20.2°K. The surface-barrier detectors jailed at liquid nitrogen temperature due to cracking of the epoxy in the lavite ring which is an integral part of the detector. The variation in pulse height, due to mono-energetic betas with temperature in partially depleted detectors, conforms to theory, being mainly due to the change of the energy necessary to create an electron-hole pair. The pulse-height change was ∼4 to 5% over the temperature range 300 to 20.2°K. However, some anomalies in the pulse height are observed in the temperature range 30 to 20.2°K during the cooling process.