  Within the t-t'-J model, the charge asymmetry in superconductivity of hole-
and electron-doped cuprates is studied based on the kinetic energy driven
superconducting mechanism. It is shown that superconductivity appears over a
narrow range of doping in electron-doped cuprates, and the superconducting
transition temperature displays the same kind of the doping controlled behavior
that is observed in the hole-doped case. However, the maximum achievable
superconducting transition temperature in the optimal doping in electron-doped
cuprates is much lower than that of the hole-doped case due to the
electron-hole asymmetry.
