The compact high-voltage power supply is developed for stimulation to promote fruiting body formation in cultivating L. edodes and Lyophyllum deeastes Sing. mushrooms. A Cockcroft-Walton (C-W) circuit is employed to generate DC high-voltage from AC 100 V plug power for the compact, easy handling and high safety use in the hilly and mountainous area. The C-W circuit is connected to high-voltage coaxial cable which works for high-voltage transmission and for charging up as energy storage capacitor. The output voltage is around 50 kV with several microseconds pulse width. The dimension and weight of the developed power supply are 0.4 × 0.47 × 1 m3 and 8.1 kg, respectively. The effect of the high-voltage stimulation on enhancement of fruiting body formation is evaluated in cultivating L. edodes and Lyophyllum deeastes Sing. mushrooms using the developed compact high-voltage power supply. The conventional Marx generator is also used for comparison in effect of high-voltage stimulation for fruiting body formation. L. edodes is cultivated with hosting to natural logs and the pulsed high voltage is applied to the cultivated natural logs. The substrate for Lyophyllum deeastes Sing. cultivation consists of sawdust. The results show that the fruiting body formation of mushrooms of L. edodes for four cultivation seasons and that of Lyophyllum deeastes Sing. for two seasons both increase approximately 1.3 times higher than control group in terms of the total weight. Although the input energy per a pulse is difference with the generators, the improvement of the fruit body yield mainly depends on the total input energy into the log. The effect for promotion on fruiting body formation by the developed compact high-voltage power supply is almost same that by the conventional Marx generator.