To address the regional applicability of heat-source tower heat pumps (HSTHPs), a mathematical model of HSTHPs was established and experimentally verified. In different thermal zones, the seasonal operation characteristics of HSTHPs were investigated in winter and summer conditions. The results showed that, the heating seasonal performance factor (HSPF) value of HSTHPs in cold zone is the lowest, but it can reach 2.40 in the winter, and the HSPF values of HSTHPs in hot-summer and warm-winter (HSWW) zone A, hot-summer and cold-winter (HSCW) zone and mild zone are all greater than 2.70. The seasonal energy efficiency ratio (SEER) values for the HSTHPs in four thermal zones are above 4.70 in summer. Except for the severe cold zone, HSTHPs have good prospects in the other four thermal zones, particularly in mild zone, with a high HSPF value of 2.77 and a high SEER value of 5.43, respectively.