The accident happened in Moo 11 village in Tambon Nong Kham.
The balloon pilot, Apiradee Thonusit, 32, and three tourists – Chairat Sopradit, 31, Phatthakorn Panpoh, 31 and their son, Watcharakiart Sopradit, 3 – were injured.
Police said a strong wind during rain caused the balloon to slip from the pole it was tied to.
Four workers tried to pull rope after it slipped but the rope broke and the balloon eventually fell on the roof of a warehouse on the opposite side of the road.