The invention provides a differential temperature and pressure tester for a horizontal well for thermal recovery. A first temperature sensor and a second temperature sensor are arranged at a certain distance for temperature measurement, and a pressure sensor probe is used for measuring pressure; a data acquisition circuit is positioned in a thermos and acquires temperature and pressure data; and the thermos protects the data acquisition circuit against the impact of high temperature, and a protective cylinder in the tester is a protective cylinder of the thermos. The differential temperature and pressure tester for the horizontal well for thermal recovery solves the problems that the uniform vapor suction and liquid production of a long horizontal segment can not be ensured, the horizontal well segment can not be fully utilized after multi-cycle of huff and puff, and many horizontal wells for thermal recovery are inefficient and the like in the prior art are solved, and has the advantages of realization of differential temperature and pressure testing of the horizontal well, high temperature high pressure resistance and reliable and secure testing.