The propagation properties of ultrashort laser pulses in water is investigated with the extended nonlinear Schrdinger equation and the electron density equation. With the theoretical model that incorporates the diffraction, normal group-velocity dispersion, multiphoton absorption, self-focusing and self-defocusing effects generated by the laser-induced eletron plasma, the spatio-temporal distribution of the on-axis laser power density and plasma density during the propagation are obtained by fininte difference method. Simulation of the underlying propagation dynamics of the ultrashort laser in water reveals that the competitive relationship between nonlinear self-focusing and self-defocusing during the pulse propagation. Moreover, the influence of laser energy, pulse duration and focusing geometry on the structure of plasma filament and the reshaping of energy fluence are discussed. The results may be benefical to understand and push forward the application of the ultrashort laser pulses in medicine, laser safety and processing in water.