To achieve effective heat dissipation for a space high-power laser diode pumping source array， a phase change thermal control system has been developed. Key components like thermal interface materials （TIM）， copper heat sinks， phase-change materials， reinforcing materials， active heaters， and space radiators have been designed and evaluated. Initially， the thermal specifications of the laser diode pumping array are outlined， followed by the thermal control design concepts. A detailed design of the thermal control system was developed， and two thermal control schemes were formulated with and without copper foam filling. Then， the two different schemes were analyzed using NX software. The first scheme reaches a peak temperature of 59.98 ℃ in 800 s， with the phase-change material surface at 47.12 ℃. The second scheme achieves a maximum temperature of 38.35℃ in 200 s and maintains thermal congruence with the phase-change temperature after 360 s， meeting the 10-40 ℃ specification. Consequently， the thermal control system for the laser diode pumping source is designed and manufactured based on the second scheme， ensuring efficient heat dissipation.