In this paper,we report the detection of the very-high-energy(VHE,100 GeV E 100 TeV) and ultra-high-energy(UHE,E 100 TeV) y-ray emissions from the direction of the young star-forming region W43,observed by the Large High Altitude Air Shower Observation(LHAASO).The extended γ-ray source was detected with a significance of～16σ by KM2A and～17σ by WCDA,respectively.The angular extension of this y-ray source is about 0.5 degrees,corresponding to a physical size of about 50pc.We discuss the origin of the γ-ray emission and possible cosmic ray acceleration in the W43 region using multi-wavelength data.Our findings suggest that W43 is likely another young star cluster capable of accelerating cosmic rays(CRs) to at least several hundred TeV.