A novel and high nonlinear photonic crystal fiber structure for supercontinuum generation was designed, and the size of the air holes in the cladding layer of the fiber is concave. The diameter of the innermost air hole d1 and the diameter of the outermost two air holes of d5 and d6 are set to a larger value to obtain high nonlinearity and low loss, respectively. In order to reduce the difficulty of optical fiber fabrication, the diameters of the second to the fourth air holes are set to be the same. Based on multipole method, the effects of air hole spacing Λ and air hole diameter on dispersion, nonlinear coefficient and loss of PCF are analyzed, and the optimal structure parameters are designed. The simulation results show that the double zero dispersion points of the fiber are 798 and 1260nm, respectively, and the maximum dispersion is 71.6ps·nm-1·km-1. In the wavelength of 0.72~1.3μm, the dispersion slope of the PCF structure is less than 0.81ps·km-1·nm-2, the nonlinear coefficient is 153.2W-1·km-1 at 780nm, and the loss is 3.1×10-3dB/km at 800nm.