In this paper, using the Buschman’s theorem for the Laplace transform, we show that the logarithmic functions ϕn(s)=1s∑i=0n(−1)iniΓ(n−i)(1)lni(s),n∈N,are the eigenfunctions of integral operators with M-Wright kernels. Some identities are also given for connections of the Mittag-Leffler functions and ϕn(s).