Let (X, B) be a log canonical pair over a normal variety Z with maximal Albanese dimension. If K X + B is relatively abundant over Z (for example, K X + B is relatively big over Z), then we prove that K X + B is abundant. In particular, the subadditvity of Kodaira dimensions κ(K X + B) ≥ κ(K F + B F ) + κ(Z) holds, where F is a general fiber, K F + B F = (K X + B)| F , and κ(Z) means the Kodaira dimension of a smooth model of Z. We discuss several variants of this result in Section 4. We also give a remark on the log Iitaka conjecture for log canonical pairs in Section 5.