OBJECTIVES: Analyze the cost-effectiveness of full-field digital mammography (DM) compared to  the screen-film mammography (SFM)  among different age groups of Mexican women METHODS: A cost-effective study was developed - from the public sector perspective- to estimate the cost per cancer detected by DM vs. SFM in the following age groups: 40-49, 50-59 and 60-69 years old. Additional costs and effects were estimated by comparing DM against SFM and expressed as incremental cost-effectiveness ratio (ICER). The outcome was the number of detected cases. Staff wages and tests cost (mammography, ultrasound and biopsy) were included. An univariate sensitivity analysis was carried out with key variables RESULTS:  DM is more expensive and more effective than SFM for breast cancer detection. Using DM for 50-59 age group is not cost- effective since it detects fewer cases at a higher cost. In the 40-49 age group, the ICER for DM was $318,828 per additional case detected, while in the 60-69 the ICER for DM was $255,636. The ICER was sensitive to the lower cost of DM CONCLUSIONS: For some age groups, DM is more effective than SFM; however, DM cost limits its use in a screening program. Evidence shows, SFM still has advantages in detecting breast cancer at an affordable cost. Further research taking into consideration social, organizational and staff training issues is important