The title compound, trans-[(RuCl2)-Cl-II(N-1-mepym)(4)] (mepym is 4-methylpyrimidine, C5H6N2), obtained from the reaction of trans,cis,cis-[(RuCl2)-Cl-II(N-1-mepym)(2) (SbPh3)(2)] (Ph is phenyl) with excess mepym in ethanol, has fourfold crystallographic symmetry and has the four pyrimidine bases coordinated through N-1 and arranged in a propeller-like orientation. The Ru-N and Ru-Cl bond distances are 2.082 (2) and 2.400 (4) Angstrom, respectively. The methyl group, and the N-3 and Cl atoms are involved in intermolecular C-H . . .N and C-H . . . Cl hydrogen-bond interactions.