A hospital-based cross-sectional study was conducted to evaluate the association between catechol-0-methyltransferase (COMT) and CYP2D6*10 single nucleotide polymorphisms (SNPs) and opioid consumption among cancer pain patients. COMT and CYP2D6*10 genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). In this study, there was no association noted between COMT genotype and dosage of morphine. The odds of moderate to high morphine use among patients with Val/Val genotype were 1.78 times higher compared to those with Val/Met genotype. For CYP2D6*10 SNPs, there was no association noted when various doses of tramadol were compared against the three CYP2D6*10 genotypes (Homozygous C/C; Heterozygous C/T and Homozygous T/T). In conclusion, there was no association seen in both the pain candidate genes, COMT (Va1158Met) and CYP2D6*10 (Pro34Ser) and opioid use among cancer pain patients.