The purpose of this study was to identify factors of intrinsic motivation that affect regular breast cancerscreening and contribute to development of a program for strategies to improve effective breast cancer screening.Subjects were residing in South Korea Gangwon-Province and were female over 40 and under 69 years of age.For the investigation, the Intrinsic Motivation Inventory (IMI) was modified to the situation of cancer screeningand was used to survey 905 inhabitants. Multinominal logistic regression analyses were conducted for regularbreast cancer screening (RS), one-time breast cancer screening (OS) and non-breast cancer screening (NS). Forstatistical analysis, IBM SPSS 20.0 was utilized. The determinant factors between RS and NS were “perceivedeffort and choice” and “stress and strain” - internal motivations related to regular breast cancer screening. Also,determinant factors between RS and OS are “age” and “perceived effort and choice” for internal motivationrelated to cancer screening. To increase regular screening, strategies that address individual perceived effortand choice are recommended.