Kosei Yamada, 39, from Saitama prefecture, was reported missing Thursday, a day after he failed to return from a solo climbing trip he made on Mount Sibayak, Kyodo News reported.
A rescue party found him in the deep ravine on the mountain Saturday. Authorities did not say how far Yamada had fallen after going off the cliff.
Dedi Hamdani, a spokesman at the search and rescue office in Medan, the capital of Indonesia's North Sumatra province, said Yamada "fractured his bones on his right leg and left hand."
Yamada was conscious when rescuers found him, Hamdani said.
The Inquirer Times reported the rescue team and Yamada had to wait until Sunday to leave the mountain because heavy fog had made conditions too slippery to move him Saturday.
The injured climber was taken to a hospital in Medan.