Telomere attrition is an important event during tumorigenesis regulated by factors including oxidative stress, mitochondrial function, DNA adducts etc. Critically short telomeres act as signal for telomerase activity in the cancer cells. To determine whether null genotype of GSTM1 gene has any association with telomere length shortening and telomerase activity, we analyzed telomere length, telomerase activity and GSTM1 polymorphism in oral tissues. We observed that malignant tissues exhibited shorter telomere length. Telomerase activity was observed in about 75% malignant tissues. 40% of the oral cancer patients exhibited GSTM1 polymorphism. Further, shorter telomere lengths were observed in patients having GSTM1 polymorphism. Also, the GSTM1 genotype showed negative correlation with telomerase activity and telomere length. Our study proposes role of GSTM1 polymorphism in telomere attrition and subsequent telomerase activity in the cancer cells. The results are suggestive of possible link between absence of GSTM1 gene and telomere length alterations.