A simple wet chemical method has been successfully used to grow zinc selenide nanorods (ZnSe NRs). The structural characteristics were investigated through TEM and XRD. The crystal unit cell of the nanorods is found to be a mixture of hexagonal phase and cubic phase and the average size of the ZnSe NR ≈10 nm. The photoluminescence spectrum shows shallow deep level visible emission due to various defect states. The interaction as well as the formation of bioconjugate of Tryptophan (Trp) and Zinc Selenide nanorods is investigated using optical spectroscopy and HRTEM images. UV–VIS and fluorescence spectra show that a spontaneous binding process occurred between Trp and Zinc Selenide nanorod. A small red shift of the absorption peak of Trp is observed due to binding of Trp with ZnSe NRs. Zinc Selenide nano rods quench the fluorescence emission of tryptophan. The Stern–Volmer quenching constant, the binding constant and the number of binding sites were also calculated.