In this paper, the effect of the next-earest (t') and third-earest (t'') hopping terms on superconductivity (SC) of the two-dimensional (2D) extended t-J model is studied by the variational Monte-Carlo (VMC) method. For hole-doped systems, the d-wave pairing correlation is suppressed by t' and t'' for underdoped cases, while it can be greatly enhanced by proper values of t' and t'' for the overdoped ones. This behavior results from the deformation of the Fermi surfaces.