For adaptive optics with curvature sensor, a close- loop wavefront correction technique based on eigenfunctions of laplacian is introduced, and the wavefront correction error is analyzed theoretically. A numerical simulation model of 61 element adaptive optics is setup. The simulations of atmospheric turbulence wavefront aberration correction are carried out. The numerical simulation results are in agreement with the theoretical analysis results, which show that the close-loop correction accuracy is lower when the amount of eigenfunctions modes is less or more because of the mode coupling increment. Finally, by analyzing the relationship between the mode amount and the condition number of retrieval matrix, a simple and practical method is proposed to choose the proper mode amount.