In this work, we prove an existence theorem of entropy solutions for nonlinear elliptic problem of the type -div(a(x, u, ∇u) + Φ(x, u)) = μ in Ω, in the setting of Musielak-Orlicz spaces. The lower order term Φ verifies the natural growth condition, no Δ2-condition is assumed on the Musielak function, and the datum μ is assumed to belong to L1(Ω)+W-1Eψ(Ω).