The monk, identified by a local rescue unit as 46-year-old Phra Ajarn Manas, was on a pilgrimage from another province and entered the Phra Sai Ngam cave on Saturday.
An unseasonal rainstorm that struck on Sunday and continued through Tuesday flooded parts of the cave while he was inside, the local rescue unit said on its Facebook page.
The unit said residents in the area told them the monk was trapped inside the cave on Tuesday afternoon. Rescue workers went in looking for him but had to call off their operation after about an hour due to rising water levels.
Pictures on the unit’s Facebook page showed the monk on Wednesday sitting inside the cave surrounded by rescue workers and having his blood pressure taken.
“At 11:30 a.m. (0230 GMT) we successfully rescued Phra Manas out of the cave,” the unit said in a post.
One of the rescue workers confirmed in a phone call that the monk was out of the cave and getting first aid.
Seventeen divers participated in the effort to find and free the monk.
Thailand made global headlines in 2018 with the high-profile rescue of 12 Thai boys and their soccer coach from a flooded cave in the northern town of Chiang Rai.