The invention discloses an electrostatic atomizing and cooling capacity evaluation device with an adjustable nozzle space angle, belonging to the technical fields of heat exchange and cooling. The electrostatic atomizing and cooling capacity evaluation device comprises an electrostatic atomizing and cooling system and a critical heat flux and heat transfer coefficient measurement system, wherein the electrostatic atomizing and cooling system comprises a big fan-shaped disc, a small fan-shaped disc, an adjustable handle, a guide rail, a first sliding block, an injection pump, a silicone rubber tube and a bracket; the critical heat flux and heat transfer coefficient measurement system comprises a purple copper bar, a K-shaped thermocouple wire, a heat insulation sleeve, a box cover, a purple copper block, an electric heating bar, a graphite felt heat insulation tray, a second sliding block, a base, a supporting block, a graphite felt heat insulation supporting block, a guide block, a voltage meter, a variable resistor and a K-shaped thermocouple. According to the electrostatic atomizing and cooling capacity evaluation device, electrostatic atomization transient-state and steady-state heat transfer experiments can be carried out on the same device at different nozzle space angles, in different target distances and with different output voltages, heating powers and cooling medium fluxes of a high voltage static generator, and the critical heat flux and the heat transfer coefficient can be measured.