A numerical investigation of the nonlinear dynamics of a passively mode-locked fiber laser containing a long period fiber grating was conducted. The model was based on the complex Ginzburg-Landau equation and the nonlinear coupled mode equations of the grating. The numerical results indicated the existence of passive mode-locking and autosoliton generation in the cavity of the laser. Both single and bound soliton pulse trains were found to exhibit period doubling bifurcations and a route to chaos as the saturated gain was increased. Furthermore, the presence of long period...