Objective　To investigate the clinical effects of posterior interosseous artery bilobate flap on repairing multiple or large skin and soft tissue defects of the hand.　Methods　4 cases of multiple skin and soft tissue defects and 5 cases of large area skin and soft tissue defects, who were treated with forearm posterior interosseous artery bilobate flap transformation from March 2011 to December 2018, were selected. All patients' wounds were accompanied by deep tissue exposure. The cutting area of flap was 4.5 cm× 5.5 cm ~ 7.0 cm× 9.0 cm in size and the donor area was directly stitched together.　Results　All flaps survived successfully. Four patients were followed up for 2 months to 2 years, with an average of 10 months.  Among them, 2 patients had overstaffed flap and underwent flap plasty half a year after operation. The flap had a good texture and the skin color was similar to the recipient area. The two-point discrimination perception of the  flap was 11~20 mm, with an average of 14 mm. The wrist joint function was not affected.　Conclusions　The application of posterior interosseous artery bilobate flap in repairing hand skin defects has the advantages of no damage to forearm main blood vessels, constant vascular anatomy, simple and convenient cutting, high survival rate, direct suture of part of donor site, similar color and texture compared with recipient site, good late function, which was an ideal method to repair hand skin defects.