No one was injured in the blaze at the store, Chutima, which is about 500 metres from the Tambon Nong Han municipal offices in Nong Han district.
Fire-fighters got the call shortly after 12.30am and spent two hours bringing it under control, but the entire shophouse was gutted and a Toyota Fortuner SUV was damaged.
Shop owner Chutima Singsuksri, 58, said she was sleeping in a ground-floor bedroom when her daughter smelled smoke.
They ran outside as the fire on the second floor quickly spread, fed by a fresh stock of school uniforms that were ready for the new semester.
The cause of the fire has yet to be determined.