The intermetallic compound PrMn6Sn6 was prepared by arc-melting and showed a HoFe6Sn6-type (group space: Immm) structure. The compound is ferromagnetic, where the Mn- and Pr-sublattices are ferromagnetically coupled,and has a Curie temperature of 325 K. The 119Sn Mssbauer spectra between 15 and 360 K were measured, and were analyzed by a simplified model according to the eight Sn crystallographic sites with different nearest-neighbors environment, and the corresponding transferred hyperfine fields and the average value dependence on temperature were obtained. The magnetic structure of the two sublattice is discussed.