ABSTRACT In the present article, a selective and efficient sensor based on organosilane functionalized graphene oxide nanocomposites has been synthesized for the fluorometric detection of tyrosine (Tyr). The 1,2,3‐triazole functionalized organosilane has been synthesized by a condensation reaction between 4‐(methylthio) aniline and alkylated benzaldehyde followed by azide‐alkyne cycloaddition reaction using Cu (I) catalyst. The synthesized organosilane has been fabricated on graphene oxide nanoparticles and the obtained graphene‐functionalized organosilane ( GO‐Silane ) was characterized by FTIR and XRD. The morphology of the nanocomposite film was analyzed using scanning electron microscopy. The photophysical properties of GO‐Silane were studied which established its selective sensor for tyrosine with the limit of detection values of 1.04 × 10 −8 M with a response time of 8 s. The strong coordinated interactions of GO‐Silane for the Tyr have been confirmed from FTIR spectra of the GO‐Silane‐Tyr complex. The competitive amino acid interference assay successfully demonstrated the selectivity of the nanocomposite sensor.