A new chiral 3D heterometallic coordination polymer [NaCo₂(L)₂(N₃)·(MeOH)]_∞ (1) (L = 2,6-pyridinedicarboxylate) was synthesized and characterized magnetically. Ferro- and antiferromagnetic interactions co-exist in 1, which results in a magnetic phase transition at the high temperature of 29 K.