In this paper, we solve a class of Neumann problems on a manifold with totally geodesic smooth boundary. As a consequence, we also solve the prescribing k-curvature problem of the modified Schouten tensor on such manifolds; that is, if the initial k-curvature of the modified Schouten tensor is positive for τ > n − 1 or negative for τ < 1, then there exists a conformal metric such that its k-curvature defined by the modified Schouten tensor equals some prescribed function and the boundary remains totally geodesic.