PURPOSE: To alleviate damage of power supply relay contact due to surge current for a capacitive load at the time of turn ON of power in a power supply circuit at the power supply section of a mobile radio telephone.

CONSTITUTION: In a power supply circuit comprising a DC power supply section 1, a load 2 having a capacitor C of predetermined capacity connected with a power supply input terminal IN3, and 8 power supply relay RL for connecting the DC power supply section 1 with the power supply input terminal IN3 through a contact (r) upon turn ON of a power switch SW, the,power switch SW is connected in parallel with the contact (r).