The invention discloses a delay chain temperature drift on-orbit correction device and a delay chain temperature drift on-orbit correction method based on FPGA. The device comprises a temperature sensor, a delay chain, a D trigger array, a decoding unit, a lookup table storage unit and a temperature drift correction control unit, wherein the temperature sensor is used for collecting real-time temperature; the delay chain is used for reading out time information of an input signal relating to a clock edge; the D trigger array is connected to the delay chain, for locking an output state of each delay unit in the delay chain when arriving the clock edge and outputting temperature coding data; the decoding unit is connected to the D trigger array, for converting the temperature coding data into binary code data and outputting; the lookup table storage unit is used for storing integral nonlinear lookup table data of the delay chain marked at a preset temperature point; the temperature drift correction control unit is connected to the temperature sensor, the decoding unit and the lookup table storage unit respectively, for achieving on-orbit correction of delay chain temperature drift. According to the delay chain temperature drift on-orbit correction device and method based on FPGA, correction of the delay chain temperature drift is achieved by fewer sources, and high time resolution capacity is ensured.