Family planning is extremely important for women with diabetes due to the various health risks and other social impacts of pregnancy in this population. Unfortunately, contraceptive use among women with diabetes remains low. This study explored the reasons influencing the decision to use contraception among East Malaysian (Sarawakian) women with diabetes. This was an exploratory qualitative study conducted at an urban public health clinic in Sarawak. Purposive sampling was used to recruit 12 women with type 2 diabetes mellitus. Semi-structured in-depth interviews were audio recorded and transcribed and then subjected to interpretive thematic analysis. Five themes appear to influence the decision to use contraception: likelihood of becoming pregnant, desired family size, personal health risks associated with getting pregnant, social implications of getting pregnant, and opinions of significant others. Among Sarawakian women with diabetes, the decision to use contraception was influenced by more than just health-related factors. Contraception counselling for this group of women should factor in their health beliefs, personal values, and social factors. Community involvement and peer support are potential strategies to improve contraception use.