Objective: To study the toxic effect of cigarette smoke on testicular tissue as a feed-back mechanism on pituitary secretion of leutinizing hormone and follicle stimulating hormone.

Patients and Methods: Present study included 25 male smokers and 7 healthy male non-smokers. For each of the subjects, blood samples were taken for determination of serum levels of leutinizing hormone and follicle stimulating hormone.

Results: Serum leutinizing hormone level was higher in smokers' group (13.28 ± 7.3797) mlU/mL, than in control group (4.1429±1.069) mlU/mL. The difference of mean between the test and control is highly significant (p < 0.005). Serum follicle stimulating hormone levels was also higher in smokers group (24.36±8.0823) mlU/mL than in control group 16.8571±3.4365) mlU/mL. Again the difference of mean is highly significant (p