BackgroundReducing unmet need for family planning by increasing the rate of modern contraceptive use is indispensable if Cameroon must meet maternal mortality targets of the Sustainable Development Goals. The objective of this survey was to estimate the rate of contraceptive use and identify factors associated with unmet need for family planning in rural Cameroon.MethodsIt was conducted a community-based cross sectional survey from February to March 2016 targeting women in a union of the Wum Health District. Participants were included by cluster multistep sampling and data collected by trained surveyors using a pretested questionnaire. Data were analysed using Epi-Info version 3.5.4. The odds ratio was used as a measure of association between unmet need for family planning and selected covariates with the statistical significant threshold set at p ≤ 0.05.ResultsAmong the 466 women included in the survey, 78.5% were legally married. The mean age of the participants was 28.7 ± 7.2 years with a mean number of years of cohabitation of 9.1 ± 7.4 years. A total of 438 women from the sample were evaluated for contraceptive use and unmet need for family planning. The rate of modern contraceptive use at the time of the survey was 13[10.1–16.6]% and about 5 in every 10 women had an unmet need for family planning (46.6[41.8–51.4]%) with 31.1% having an unmet need for spacing and 15.5% an unmet need for limiting births. The potential demand for contraception was estimated at 45.9% with only 39.8% of this demand met.When controlled for age, monthly revenue, occupation and partner’s level of education, discussion of family planning within the couple (OR = 0.66[0.44–0.97], p-value = 0.032), and partner’s approval of contraception (OR = 0.66[0.45–0.97], p-value = 0.035), were found to be significantly associated with decreasing unmet need for family planning.ConclusionWith the very low rates of modern contraceptive use and potential demand for contraception in the Wum Health District, the rate of unmet need for family planning is still very high. Non discussion of family planning within the couple, and disapproval of contraception by the partner are significantly associated with high unmet need for family planning. More of couple-based family planning interventions should be encouraged.Electronic supplementary materialThe online version of this article (10.1186/s12905-018-0660-7) contains supplementary material, which is available to authorized users.