In the title coordination compound, [Cu(NCS)(C(9)H(7)N)(C(18)H(15)P)](n), the Cu(I) atom is tetra-hedrally coordinated by one N atom from an isoquinoline ligand, one P atom from a triphenyl-phospane ligand, and one N and one S atom from two thio-cyanate anions. The thio-cyanide anions bridge the Cu(I) atoms into a chain along [100]. π-π inter-actions between the pyridine and benzene rings of the isoquinoline ligands connect the chains [centroid-to-centroid distance = 3.722 (3) Å].