One novel complex Mn2(phen)2(p-CBA) 4(H2O) has been hydrothermally synthesized from p-chlorobenzoic acid (p-CBA), 1,10-phenanthroline (phen) and anhydrous manganese(II) sulfate and then characterized. Crystal data for this complex: monoclinic, space group C2/c, with a = 2.3416(3), b = 1.5604(2), c =1.5605(2) nm, β = 121.048(2)°, V= 4.8849(12) nm3, Dc = 1.510 g/cm3, Mr = 555.26, Z = 8, μ = 0.798 mm -1, F(000) = 2256, GOOF = 1.032, the final R = 0.0393 and wR = 0.0816. The crystal structure shows that two neighboring manganese(II) ions are lin...