Human teeth are the hardest and the most stable and durable tissues in the body. Teeth can be identified even after complete decomposition. They are therefore invaluable for identification of sex and age from fragmentary adult skeleton. The present study aimed to investigate the accuracy with which gender can by differentiated by utilizing computed mandibular canine width measurements. Periapical radiographs for the permanent mandibular canines on both sides were obtained from 60 Egyptian individuals (30 males and 30 females).Their age ranges between 18 and 21 years. The developed radiographs were digitized and analyzed using the Load and Measure Program. Measurements obtained in this study include, maximum mesiodistal crown width (W1), root width at cementoenamel  junction "CEJ" (W2), root width midway between "CEJ" and mid root level (W3), root width at mid root level (W4) and root width midway between mid root level and tooth apex (W5). The statistical analysis of the obtained data showed that, the mean values of right and left canines' measurements were statistically larger in males than females regarding whole variables. The maximum mesiodistal crown width (W1) was the variable with the greatest sex differences in both sides (d/s=5.135 for right and 5.474 for the left). The distance between sex means (d/s) was higher in left canine more than the right regarding all variables. In both sides the maximum mesiodistal crown width (W1) showed the higher rate of accuracy (100%). The lowest rate of accuracy was obtained from root width at mid root level (W4), (58.33% for right & 86.34% of left). The mesiodistal  crown  width  (W1)  and  root  width  midway  between  cementoenamel  junction and  mid root  level  (W3)  were  the  most  sensitive  variables  for  in  both sides (100%). Meanwhile, mesiodistal crown width (W1) and root width at cementoenamel junction (W2) were found to be the most specific variables  in  both  sides  (100%).  The  present study establishes an accurate method for sex prediction from mandibular canines that depend upon taken computed measurements from different levels and  so, it  can  be  applied  if  canine  tooth  or even a part of it was subjected to forensic postmortem examination.