We studied magneto-transport properties of Cobalt-AlOx-permalloy magnetic tunnel junctions with the insertion of cyclic phenylene macrocycle [6]Cyclo-2,7-naphthylenes (CNAP) to investigate the effect of interfacial properties of -conjugate organic molecule / ferromagnetic metal. Magnetoresistance ratio of the junction with no CNAP molecular layer was 2.1% at 300K, whereas the magnetoresistance ratio increased up to 5.6% at 300 K with insertion of the 3-nm-thick CNAP layer. The result is discussed in terms of spin polarization enhancement due to -d hybridization at the interface of CNAP / NiFe.