Some reactive dyes (6a-6l) having Quinazolin-4(3H)-one reactive system have been synthesized by coupling of diazotized 3-(4-(5-(4-aminophenyl)-1,3,4-oxadiazol-2-yl) phenyl)-4-oxo-2-phenyl-3,4-dihydroquinazoline-6-sulphonic acid with cyanurated coupling components such as H-acid, J-acid, N-methyl J-acid, Gamma acid, Peri acid, Sulpho Tobias acid, Koch acid, Bronners acid, Chicago acid, K-acid, N-Phenyl J-acid and M-acid. The synthesized dyes were characterized by nitrogen elemental analysis, IR, and 1H-NMR spectra. They were applied on wool, silk, and cotton fibres. Their dyeing properties, fastness properties, and colorimetric data (L*, a*, b*, C*, H*, and K/S) have also been investigated.