In order to improve the sensitivity of surface acoustic wave(SAW) pressure sensor based on langasite(LGS),a SAW sensor of point pressure forced package structure is studied.The finite element method(FEM) and the perturbation method is theoretically adopted.The stress and strain of LGS substrate induced by pressure are calculated by FEM, and the pressure sensitivity is obtained by substituting the stress and strain into linear electroelastic equations and first order perturbation equation.The calculated normalized pressure sensitivity is 0.067×10-6/psi within 0～0.4 MPa,and about 9 times higher than the reported SAW LGS pressure sensor of the cavity structure.A SAW sensor based on LGS (0°,138.5°,26.7°) is designed, and experimental result matches the theoretical analysis.