In this paper, we investigate the effects of a classical gravitational field on the dynamical behaviour of nonlinear atom-field interaction within the framework of the f -deformed Jaynes-Cummings model. For this purpose, we first introduce a set of new atomic operators obeying an f -deformed su(2) algebraic structure to derive an effective Hamiltonian for the system under consideration. Then by solving the Schrödinger equation in the interaction picture and considering certain initial quantum states for the atomic and radiation subsystems, we analyze the influence of gravity on the temporal evolution of the atomic population inversion, atomic dipole squeezing, atomic momentum diffusion, photon counting statistics, and deformed quadrature squeezing of the radiation field.