Background: While women representation and sex disparities in National Comprehensive Cancer Network (NCCN) has been studied in a limited set of CPGs, the current sex representation and disparities among panelists of all NCCN and European Society of Medical Oncology (ESMO) CPGs has not been studied. Our study evaluates current sex disparities and women representation for all 60 NCCN and 79 ESMO CPGs. Methods: We examined the Sep. 2020 version of the NCCN CPGs and Nov. 2020 version of the ESMO CPGs on their respective websites. Using CPGs for each cancer type and respective panelists, we catalogued the number of females versus male panelist. We discerned the sex of the panelists based on google search and their affiliated institutional websites. Results: The number of female and male CPG panelists was reviewed for 60 NCCN and 79 ESMO CPGs inclusive of all cancers by site, detection prevention and risk reduction, supportive care, and guidelines for specific population. Of the total 2522 NCCN panelists,1400 (56%) were female and 1122 (44%) male. 35 (58%) NCCN CPGs had predominant female representation (>50% of the members being female) whereas 24 (40%) NCCN CPGs were male predominant (>50% of the members being male). NCCN solid tumors has 24 CPGs with 1082 panelists, total male panelists were 550 (50.8%) and female panelists 532 (49.2%). NCCN hematological malignancies has 14 CPGs with 594 total members of which, 258 (43.4%) were male and 336 (56.6%) female. Cancers specific to women (breast, cervical/uterine, ovarian and bone) had higher proportion of female panelists. ESMO has a total of 79 CPGs with 816 panelists. Of these, 582 (71.3%) were male and 234 (28.7%) female. CPGs with prominent female representation were Breast cancer (86.7%) and Hereditary syndromes (85.7%). Remainder of the 77 CPGs were male predominant. Gynecological cancer CPG had 46.9% female panelists. ESMO solid tumors has 39 CPGs with 474 panelists. Of these, 327 (69%) were male and147 (31%) female. ESMO hematological malignancies had 17 CPGs with a total of 144 panelists of which 122 (84.7%) are male and 22 (15.3%) female. Conclusion: The NCCN CPG panels have greater than 50% female representation among its 60 CPGs indicating that there is no underrepresentation of women in NCCN guidelines. Whereas in ESMO, females were underrepresented in their CPGs with less than 30% female panelists. Factors contributing to underrepresentation of women in ESMO CPGs will need to be explored.