The provincial earthquake bureau told reporters that the shaking was acutely felt in 18 townships around the city of Baoshan, in Tengchong county.
Several houses were reported wrecked by the quake. Relief officials dispatched crews, supplies and tents to help those affected.
A 5.8 magnitude quake just to the south in the same region on March 10 killed 24 people and toppled about 1,200 homes.
A 4.8 magnitude quake in the same area on February 1 damaged more than 200 homes.