Therapeutic cannabis is a subject which many researchers are very interested in all over the world. The effect of main compound of Cannabis is investigated to treat many diseases. Arachidonate 5-lypoxygenase (5-LO) is implicated in cancer progression, inflammation, tissue damage and other sickness. Commonly to inhibit 5-LO enzyme a famous drug Zileuton is used. In our work we compare inhibition of 5-LO by main compounds of cannabis using tools such as molecular mechanics, molecular dynamics and molecular docking by using MOE software (Molecular Operating Environment) [1]. Obtained results show that main cannabinoids inhibit 5-LO better than Zileuton.