In the title coordination polymer, {[Cu(CN)(C(12)H(10)N(2))]·0.5C(2)H(5)OH}(n), there are two Cu(I) ions, two 1,10-phenanthroline (phen) ligands and two cyanide ions in the asymmetric unit along with a highly disordered ethanol solvent mol-ecule, which was modelled as being disordered over two sets of sites in a 0.829 (7):0.171 (7) ratio. The orientation/ordering of the C and N atoms of the cyanide ions could not be determined in the present refinement and they were modelled as being statistically disordered. Both copper ions are coordinated by an N,N'-bidentate phen ligand and two cyanide ligands, generating distorted tetra-hedral CuN(2)Q(2) (Q = C or N) tetra-hedra. The μ-cyanide ligands link the metal ions, forming a zigzag chain propagating in [001]. The chains are cross-linked by numerous aromatic π-π stacking contacts between adjacent phen rings [minimum centroid-centroid separation = 3.620 (3) Å].