In this paper, we study the nonlinear parabolic problem: ∂b(x, u) ∂t − div(a(x, t, u, ∇u)) + div(φ(x, t, u)) = f where b(x, u) is unbounded function of u, the term −div a(x, t, u, ∇u) is a Leray-Lions operator and the function φ is a nonlinear lower order and satisfy only the growth condition. The second term f belongs to L 1 (Ω × (0, T)). The main contribution of our work is to prove the existence of a renormalized solution.