Background of the study: Unwanted pregnancy is one of the demographic problems that creaternmaternal death, abortion, low birth weight, preterm birth and infant mortality, unsafe abortions, andrnpoor maternity care in developing countries like Ethiopia.rnObjective: To assess the prevalence of unwanted pregnancy and associated socio-economic andrndemographic factors among pregnant women attending Antenatal care services in selected publicrnhealth centers of Arada sub-city, Addis Ababa, Ethiopia, 2021.rnMethod: An institutional-based cross-sectional study design with mixed (quantitative and qualitativernapproaches) was used. The study was conducted between May and June 2021. Systematic randomrnsampling technique was used to select the study subjects. The sample size determined for the study wasrn314. A standardized interviewer-administered questionnaire was used to gather information from studyrnparticipants. Data were cleaned, entered into, and analyzed by Statistical Package for Social Sciencesrn(SPSS) version 24. Descriptive statistics such as frequencies, percentages, and crosstabs were used torndescribe the variables of interest. Furthermore, logistic regression including bivariate and multivariaternanalysis was used to identify the determinants of an unwanted pregnancy. Results are presented inrntables, texts, and figures.rnResults: A total of 308 pregnant women participated in the study making the response rate 98%.rnAmong respondents, unwanted pregnancy was found to be 30.2% while 69.8% of the pregnancy wasrnwanted. Those who had missed contraceptive pills AOR [0.257 (0.086, 0.768)], respondents who arernmarried women AOR [10.09 (1.81, 56.16)] and respondents who had higher education AOR [0.14rn(0.03, 0.70) were significantly associated with an unwanted pregnancy (p