According to an agency's report, the incessant rains over the past three days caused flash floods and collapsed houses.
The death toll recorded by Brig Kamran Zia, a member of the National Disaster Management Authority, was 12 in northwest's semi autonomous tribal region, 8 in Khyber Pakhtunkhwa province, and 3 in the Pakistan-held part of the disputed Kashmir region.
"At least 12 people died in central Punjab province, 10 in southwestern Baluchistan, and eight in southern Sindh" , he said.
He also told agency that flooding was bad in Pakistan's largest city, Karachi, because of the southern city's faulty drainage system. Around 19 people have reportedly died in Karachi.
Meanwhile, the Pakistani disaster relief officials have issued fresh flood warnings as more thunderstorms and heavy rains are expected on Monday and some rivers may flood.
Pakistani Prime Minister Nawaz Sharif has sent three of his cabinet ministers to inspect damage in flood-hit areas.
Pak Army has launched relief and rescue operations.
(With Agency inputs)