In this study, inhibition of human carbonic anhydrase (h CAI) enzyme was investigated in four different organic synthesis compounds. Two of these compounds are [(4-amino-3-phenyl-5-p-tolyl-4H-1,2,4-triazole) (1 ) and (2,5-diphenyl-1,3,4-oxadiazol) (2)] was previously synthesized by our group, while the other two were newly synthesized [(4-methyl-N-(1-tosyl-1H-1,2,4-triazol-3yl)benzene sulfonamide) (3) and (4-(( 5-) bromo-2-hydroxy benilidene)amino)-5-(4-chlorophenyl)-2,4-dihydro-3H-1,2,4-triazol-3-one) (4)]. In this study, carbonic anhydrase enzyme inhibition was examined and inhibition values were measured using the Ki and IC50 values of the enzyme. IC50 values measured by esterase activity were detected in the range of 0.023 to 0.095 mM for h CAI, while compound 4 showed the highest inhibition value. Ki values for h CA I was observed between 0.046 and 0.056 mM, and the highest Ki value was also measured for again compound 4.