For application of PT100 in industrial temperature measurement, the transfer function method based nonlinear correction is proposed and its superiority and practicality is verified. Multipoint temperature program is designed based on threewire PT100, using C8051F410 processor as the core, using the onchip ADC timeshared control, and multichannel temperature acquisition is realized. Practice showed that this scheme can increase the temperature measurement accuracy and efficiency of system development, and can be widely used in industrial control field.