Abstract. The main purpose of this paper is to study the existence of solutions for the following hybrid nonlinear fractional pantograph equationwhere α ∈ (0,1) , ϕ and ρ are functions from [0,1] into itself and D α 0+ denotes the RiemannLiouville fractional derivative. The main tool of our study is a generalization of Darbo's fixed point theorem associated to measures of non-compactness. Also, we present an example illustrating our results.