This work was planned to investigate the genetic effect of the oral contraceptive drug “Anovlar 1" on human chromosomes. In order to achieve such a purpose, Heparinized blood samples were collected from healthy adults. Lymphocyte cells were isolated and cultures were performed at 37 ؛C for 72 hrs. The results obtained showed that the tested drug was proven to be a positive clastogen, since C-metaphases; stickiness; fragments and polyploidy were observed in a concentration-response relationship. The result, however, revealed that the tested drug has clastogenic activity upon human genome.