The invention provides a biomass heat- and solar-energy multistage cooling, heating and power combined supply system and belongs to the technical field of energy resource and environment. The biomass heat- and solar-energy multistage cooing, heating and power combined supply system comprises a heat transfer fluid circulation loop, a power generation loop, a cooling and power combined supply loop, a solar energy circulation loop, a biomass burning furnace smoke discharge pipeline, a heat and hot water supply loop and a cooling water loop, wherein the power generation loop is composed of a direct-contact type evaporator, a first turbine, a first heat regenerator, a condensation evaporator, a first liquid storage tank and a first working medium pressurizing pump, and the solar energy circulation loop comprises a heat storage and exchange device, a second heat transfer fluid circulation pump and a solar heat accumulation heater. The biomass heat- and solar-energy multistage cooling, heating and power combined supply system is high in heat exchange efficiency, gradient utilization of heat is realized, energy utilization efficiency is high, cooling, heat and power can be continuously and stably output, the direct-contact type evaporator is simple in structure and the like; output load of a biomass burning furnace and output load of the heat storage and exchange device can be adjusted according to needs of heat users for cooling load, heat supply load and power supply load.