: Introduction Recently the rapid growth of population become a huge problem. Government efforts to control the population is KB programs, one of the common offered contraception is KB Pills. Acceptor knowledge became one of the critical success of the contraceptives in use. The higher the acceptor knowledge resulted in compliance in taking KB pills. This research is analytic observational with cross sectional design research. Population in this research is 50 mothers. Sampling technique that use is simple random sampling which deliver 44 mothers as sample. Result of this research using chi square with alpha < 0,05. The research result shows that 5 respondent from 20 respondent with a good level of knowledge is non-compliance with the drinking KB pills schedule. Meanwhile 19 respondent from 24 respondent with low level of knowledge is non-compliance with the drinking KB pills schedule. Probability value is ρ: 0,001. The Conclusion is a relationship between mother's knowledge and the compliance of KB pill consume in Puskesmas Modayag, East Bolaang Mongondow district.