Clinoptilolite is well suited for adsorption applications due to its large amount of pore space, high resistance to extreme temperatures, chemically neutral basic structure and also its availability and low cost. In this project the relationship between odorant concentrations in the inner atmosphere of two restaurants were studied with respect to time by using a filter which has the clinoptilolite as packing material. "Olfactometer TO7" was used for determination of odorant concentrations. Results of the experiments have shown that in one of the restaurants the initial concentration was 375 OU/m(3) at the start of the experiment. As time progressed during experiments, the odour concentration decreased and after 2 hours a concentration of 100 OU/m(3) was obtained. In the second restaurant the initial odour concentration in the environment was 15000 OU/m(3) and it fell to 400 OU/m3 in 20 minutes and it continued to go down to 90 OU/m(3) in 120 minutes. The odour removal efficiencies in 2 hrs were calculated as 73.3% and 97.3% for the first and the second restaurants, respectively.