Dynamic behavior of the propagation of incoherent optical spatial solitons in a nonlocal nonlinear medium is investigated. By means of the Hirota method, we obtain the soliton solutions, based on which we find that vertical bar psi vertical bar is positively related to n(0), but inversely related to omega and kappa, whereas Delta n is independent of them, with psi as the slowly varying amplitude of the beam, Delta n as the refractive index change, n(0), omega, and kappa as the unperturbed refractive index, frequency of the propagating beam, and beam intensity distribution, respectively. Head-on and bound-state soliton interactions are both given, and one interaction period decreases with omega and kappa increasing in the bound state one. With the external perturbations taken into consideration, the associated chaotic motions of the perturbed model are studied, and the corresponding power spectra and phase projections are obtained. Both the weak and developed chaotic states are investigated, and the difference between them roots in the relative magnitude of nonlinearities and perturbations. Such chaotic motions can be weakened via increasing omega and kappa or decreasing n(0). Periodic motion is obtained with the nonlinearities and perturbations balanced.