A water temperature control method for a swimming pool heat pump system, wherein the heat pump system comprises an inverter compressor, and the method comprises: 101, 201: obtaining an external ambient temperature and adjusting a heating temperature according to the external ambient temperature to obtain a target heating temperature; 102, 202: detecting an inlet water temperature of the swimming pool heat pump system, and determining an absolute value of a temperature difference between the inlet water temperature and the target heating temperature; and 103: determining a target operating frequency band of the swimming pool heat pump system according to the absolute value of the temperature difference, controlling the inverter compressor in the swimming pool heat pump system to heat water in a to-be-heated container based on the target operating frequency band, and placing heated water in the to-be-heated container into the swimming pool by using a circulating pump, wherein the obtaining an external ambient temperature and adjusting a heating temperature according to the external ambient temperature to obtain a target heating temperature comprises: detecting a current external ambient temperature by using a preset ambient temperature sensor; if the external ambient temperature is less than or equal to a first ambient temperature threshold, determining a first preset temperature as the target heating temperature; if the external ambient temperature is greater than the first ambient temperature threshold and is less than or equal to a second ambient temperature threshold, determining a corresponding target heating temperature according to a preset curve, wherein the preset curve is used to indicate an inverse ratio relationship between the target heating temperature and the ambient temperature; and if the external ambient temperature is greater than the second ambient temperature threshold, determining a second preset temperature as the target heating temperature, wherein the second preset temperature is less than the first preset temperature, wherein: a slope of the preset curve is K, K = TT 1 − TT 2 AT 1 − AT 2, wherein TT1 is the first preset temperature, TT 2 is the second preset temperature, AT 1 is the first ambient temperature threshold, and AT2 is the second ambient temperature threshold. 101, 201: obtaining an external ambient temperature and adjusting a heating temperature according to the external ambient temperature to obtain a target heating temperature; 102, 202: detecting an inlet water temperature of the swimming pool heat pump system, and determining an absolute value of a temperature difference between the inlet water temperature and the target heating temperature; and 103: determining a target operating frequency band of the swimming pool heat pump system according to the absolute value of the temperature difference, controlling the inverter compressor in the swimming pool heat pump system to heat water in a to-be-heated container based on the target operating frequency band, and placing heated water in the to-be-heated container into the swimming pool by using a circulating pump, wherein the obtaining an external ambient temperature and adjusting a heating temperature according to the external ambient temperature to obtain a target heating temperature comprises: detecting a current external ambient temperature by using a preset ambient temperature sensor; if the external ambient temperature is less than or equal to a first ambient temperature threshold, determining a first preset temperature as the target heating temperature; if the external ambient temperature is greater than the first ambient temperature threshold and is less than or equal to a second ambient temperature threshold, determining a corresponding target heating temperature according to a preset curve, wherein the preset curve is used to indicate an inverse ratio relationship between the target heating temperature and the ambient temperature; and if the external ambient temperature is greater than the second ambient temperature threshold, determining a second preset temperature as the target heating temperature, wherein the second preset temperature is less than the first preset temperature, wherein: a slope of the preset curve is K, K = TT 1 − TT 2 AT 1 − AT 2, wherein TT1 is the first preset temperature, TT 2 is the second preset temperature, AT 1 is the first ambient temperature threshold, and AT2 is the second ambient temperature threshold. detecting a current external ambient temperature by using a preset ambient temperature sensor; if the external ambient temperature is less than or equal to a first ambient temperature threshold, determining a first preset temperature as the target heating temperature; if the external ambient temperature is greater than the first ambient temperature threshold and is less than or equal to a second ambient temperature threshold, determining a corresponding target heating temperature according to a preset curve, wherein the preset curve is used to indicate an inverse ratio relationship between the target heating temperature and the ambient temperature; and if the external ambient temperature is greater than the second ambient temperature threshold, determining a second preset temperature as the target heating temperature, wherein the second preset temperature is less than the first preset temperature, wherein: a slope of the preset curve is K, K = TT 1 − TT 2 AT 1 − AT 2, wherein TT1 is the first preset temperature, TT 2 is the second preset temperature, AT 1 is the first ambient temperature threshold, and AT2 is the second ambient temperature threshold.