Abstract:Contraception is important for reducing the rate of unplanned pregnancy in all ages, some abortions, allowing a spacing of families, and improving the health of women. Studies stressed that successfully using contraception to prevent an unplanned pregnancy is a complex undertaking that requires alignment of multiple domains: knowledge about available methods, personal attitudes and beliefs, subjective norms, and a person's ability to obtain and actually use a birth control method. Advance practice nurses in many settings can prescribe and insert contraceptive devices. The present study aimed to determine women's knowledge level regarding oral contraception pills (OCP) and intrauterine device (IUD) in Riyadh, and assessing the factors associated with this knowledge; either socio-demographic characteristics or gynecological and obstetrical history. A cross-sectional prospective study conducted among Saudi women attending ten primary care centers in Riyadh, from January to March 2016. Two hundred women participated, the women aged ≥18 years who agreed to contribute to a study concerning contraception. A structured questionnaire was developed and used to compiled respondent socio-demographic, gynecological and obstetric history. It also assessed defendant's knowledge regarding oral contraceptive pills and intrauterine device. Most of the study sample (97.5%) were educated and only (2.5%) illiterate. About (75%) were employees, (23%) were bachelors. (66%) Are using or at a point used contraceptives. Among those who used contraceptive methods, (61%) used OCP and (8%) used IUD. The primary source of women's knowledge regarding contraceptives was the health care team; doctor, nurse, and pharmacist. Women's average knowledge score level regarding contraceptives was relatively low; 39.85 of OCP and 33.40 of IUD. Multiple regression analysis showed that age, educational attainment, parity and use of contraceptives influencing knowledge level regarding OCP or IUD. In conclusion, oral contraceptive pills (OCP) are the most commonly used contraceptive/ than the intrauterine device (IUD) so nurses should develop more effective education about contraceptive methods.