Objective: To explore the factors associated with the uptake of mammography screening in Reunionese women aged 50-65 years. Methods: This study included all women aged 50 to 65 years participating in a population-based cross-sectional study "FOSFORE". Participants were recruited between March and June 2017 using two sampling frames. The first frame consisted of households with a landline telephone, with or without a mobile line, by first randomly generating a telephone number and then randomly selecting an individual from among all eligible women in the household. The second sampling frame was constituted of women with an exclusive mobile line, who were selected directly if they met the eligibility criteria. Data were weighted for age and socio-professional status to ensure representativeness at the Reunion Island level. Weighted logistic regression was used to calculate odds ratios while adjusting for confounders. Results: 417 women were included in the study; 63.8% were up to date with guidelines on mammography screening and 36.2% were not up to date. Four factors were significantly associated with mammography screening, with an adjusted odds ratio of 2.92 (95% CI 1.51-5.61) for not having an Active Solidarity Income, 1.98 (95% CI 1.22-3.23) for having a regular gynecological follow-up by a physician, 6.53 (95% CI 3.23-13.21) for performing a Pap smear test in the past two years, and 2.07 (95% CI 1.21-3.52) for having an adequate literacy level (HLQ3). Conclusion: The findings of this study suggest that higher socio-economic status is an indicator of participation in mammography screening in La Réunion, and future educational and intervention programs should target women in deprived areas.