PURPOSE: To evaluate an educational effect of the mammography boot camp (MBC) for radiology residents and analyze affecting factors. MATERIALS AND METHODS: Between December 2014 and February 2015, radiology residents in 16 institutions performed the MBC program. We compared the educational effect (score difference between pre- and post-camp test) using 25 case series and analyzed the affecting factors including institution, grades of residents, training periods, presence of sub-specialized breast staff, breast density, and types of cases. RESULTS: The mean scores of 92 residents were 52.80 ± 18.10 and 72.50 ± 12.91 in the pre- and post-camp test, respectively (p = 0.001). There was no significant difference of educational effect according to institution (19.70 ± 16.31), grade, or training period. Although the educational effect of non-trainees was superior to that of trainees (28.10 ± 17.55 vs. 15.90 ± 14.22; p = 0.001), the scores of trainees were higher than those of non-trainees. The diagnostic accuracy showed more improvement in a fatty breast and cases with microcalcifications than compared with others. CONCLUSION: The MBC showed an effective educational result for radiology residents when interpretating a mammography. It was helpful even for non-trainees. The institution, grades training period, and presence of sub-specialized breast staff did not affect the educational effect.