Background: Even though healthcare-seeking interventions potentially reduce child mortality from easily treatable diseases, significant numbers of children die without ever reaching a health facility or due to delays in seeking care in Ethiopia. Though there was fragmented evidence on the proportion of mothers' healthcare-seeking behavior and associated factors for common childhood illnesses in Ethiopia, the national level is unknown. Therefore, this systematic review and meta-analysis estimated the pooled proportion of mothers' healthcare-seeking behavior and associated factors in Ethiopia from 2008–2019. Methods: We systematically searched the databases: PubMed/MEDLINE, Google Scholar, and Science Direct for studies conducted in Ethiopia on mothers’ health care seeking behavior since 2008. We have included observational studies, which were published between 2008 and 2019. The report was compiled according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The quality of included studies was scored based on the Newcastle Ottawa quality assessment scale adapted for cross-sectional studies. The data were extracted in Microsoft excel and analyzed using Stata version 14.1 software. We employed a random-effects model to estimate the pooled proportion of mothers' healthcare-seeking behavior in Ethiopia. The presence of statistical heterogeneity within the included studies was evaluated using the I-squared statistic. We used Egger’s regression test to identify evidence of publication bias. The pooled proportion with a 95% confidence interval (CI) was presented using tables and forest plots. Result: We screened a total of 581 articles. Of these, 14 studies were included in the final systematic review and meta-analysis. In Ethiopia, the pooled proportion of mothers' health care seeking behavior was 50.24% (95% CI: 37.13, 63.35%). Less than 5 kilometers from a health facility (OR, 2.07; 95% CI: 1.50, 2.87), mothers who were aware of common childhood illnesses (OR =2.06; 95% CI: 1.45, 2.91, mothers who had educational levels of primary school and above (OR = 1.82;95% CI: 1.36, 2.43), caregivers at a higher wealth index category (OR = 2.01; 95% CI: 1.33. 3.24) were significantly associated with health care seeking behavior of mothers/caregivers. Conclusion: Overall, in Ethiopia healthcare-seeking behavior of mothers/caregivers for common childhood illnesses is low. Awareness, perceived illness severity, distance from a health care facility, and mothers/caregivers’ level of education were predictors of mothers' healthcare-seeking behavior. Accordingly, increasing the proximity of health facilities and educate mothers/caregivers about the importance of healthcare-seeking behavior were recommended to improve healthcare-seeking behavior.