Background: Utilization of family planning services improves women’s reproductive health outcomes. Long-acting reversible contraceptive (LARCs) methods, in particular, prevent unwanted pregnancy and significantly reduce maternal mortality and morbidity. In Ethiopia utilization of LARCs was very low. Therefore, this study was aimed at assessing the utilization of LARCs and associated factors among reproductive-age women in Wondo Genet District, Southern Ethiopia. Method: Institution based cross-sectional study was conducted from 15 May to 15 August 2020 among reproductive-age women. A systematic sampling method was applied to recruit 376 women and the sample size was allocated to health centers proportionally. Data collection was conducted by trained collectors using pretested and structured questionnaires. Data coded and entered into EPI Info 7 and the analysis was done using SPSS version 25. Binary and multiple logistic regression analyses were done. Statistical significance was declared with P < 0.05. Result: The utilization of LARCs was 37.8% (95% CI: 32.9-42.7). The multivariable analysis showed that odds of the utilization of LARCs were increased among reproductive-aged ≥25 years (Adjusted odds ratio (AOR) = 2.21, 95% CI: 1.04, 4.41), gave birth to ≥3 live births (AOR = 2.2, 95% CI: 1.2, 4.04), employed (AOR = 1.92, 95% CI: 1.17, 3.14), earned high monthly income (AOR = 2.02, 95% CI: 1.25, 3.26) and discussed contraceptive methods with their husbands (AOR = 2.87, CI: 1.68, 4.89]. Conclusions: Utilization of LARCs was low. The odds of the utilization of LARCs were increased in women aged ≥25 years, gave birth to 3 or more children, earned high monthly income, and discussed with their husbands about contraception methods.