Disclosed is a method for manufacturing a semiconductor light-receiving device having high reproducibility and reliability. Specifically disclosed is a semiconductor light-receiving device 100 with a mesa structure wherein a light-absorbing layer 6, an avalanche multiplication layer 4 and an electric-field relaxation layer 5 are formed on a semiconductor substrate 2. The light-absorbing layer 6, avalanche multiplication layer 4 and electric-field relaxation layer 5 exposed in the side wall of the mesa structure are protected by an SiNx film or an SiOyNz film. The hydrogen concentration in the side wall surface of the electric-field relaxation layer 5 is set at not more than 15%, preferably not more than 10% of the carrier concentration of the electric-field relaxation layer 5.