Abstract
In this paper we introduce a q-fractional variant of nonlinear Langevin equation of different orders with q-fractional antiperiodic boundary conditions. The nonlinearity in the proposed problem involves an integral term (a Riemann-Liouville type q-integral) and a non-integral term. Some existence results for solutions of the given problem are established by means of classical tools of fixed point theory. An illustrative example is also presented.