The invention belongs to the technical field of heating ventilation air conditioning application, and relates to an indoor thermal comfort degree regulation and system energy-saving process, in particular to a solar solid humidity-adjusting system in winter and summer. The system consists of a first solid humidity-adjusting module, a second solid humidity-adjusting module, a solar heat collection module, a phase change heat storage module, a blower, an exhaust fan, a solar heat collection recycle pump and a heat storage recycle pump. Other auxiliary equipment comprises a first electric two-way valve, a second electric two-way valve, a third electric two-way valve and a fourth electric two-way valve on water pipelines, a first electric air valve, a second electric air valve, a third electric air valve, a fourth electric air valve, a fifth electric air valve, a sixth electric air valve, a seventh electric air valve and an eighth electric air valve on air pipelines, and the like. According to the system, solar energy is fully utilized, and continuous and stable operation for dehumidification in summer, humidification in winter and heating in winter by fresh air is realized.