The nonlinear evolution equation of the resistive m≥2 tearing modes near their linear thresholds is derived as ?-Q2A+K/2A2à-Q2(δ△1e)/(△1e)A3=0 where the quasilinear approximation has been used; A is the mode amplitude; Q and K are the dimensionless linear growth rate and wave vector; △e and δ△1e are the linear and nonlinear discontinuities of the logarithmic derivatives. The nonlinear time evolutions of the modes are discussed in detail. No bifurcation solution exists for a symmetrical sheet pinch model.