We show that the parabolicity of a manifold is equivalent to the validity of the 'divergence theorem' for some class of δ-subharmonic functions. From this property we can show a certain Liouville property of harmonic maps on parabolic manifolds. Elementary stochastic calculus is used as a main tool. 0. Introduction. This note was inspired by the following two results concerning the Liouville property of harmonic maps and subharmonic functions of finite energy.THEOREM 1 (Cheng-Tam-Wan [5]). Let f : M → N be a harmonic map of finite energy from a complete Riemannian manifold M to a Cartan-Hadamard manifold N (i.e. N is a simply connected, complete Riemannian manifold of nonpositive sectional curvature). If M does not admit nonconstant bounded harmonic functions, then f is constant.They actually showed that under the assumption on the source manifold, the image of the harmonic map should be bounded. The above result is obtained by combining this with a result due to Kendall [21] to the effect that if M does not admit nonconstant bounded harmonic functions and f is bounded, then f is constant.The second is a divergence theorem due to Takegoshi.THEOREM 2 (Takegoshi [25]). Let M be a complete Riemannian manifold and u a C 2 -function on M. Suppose that u satisfieswhere V (t) is the Riemannian volume of a geodesic ball of radius t. Then ( u) + ∈ L 1 (M) and M udv = 0 .