Background Exclusive breastfeeding is the practice of a woman feeding an infant for six months, which has an irreplaceable benefit. However, the practice is still low with salient factors in a different place. Therefore, this study was aimed to assess exclusive breastfeeding practice and associated factors among mothers of having children less than two-years of age in Northeastern Ethiopia, 2019.Methods A community-based cross-sectional study was conducted with a sample size of 423 in Northeast Ethiopia from March 12 to December 18, 2019. An interviewer-administered questionnaire was used to collect the data. The binary logistic regression model was used to determine the association between dependent and independent variables.Result The prevalence of exclusive breastfeeding practice was 75.5%(95%CI:73.5,81.5%). Married mothers 2.57(1.688, 5.654), mothers with antenatal care follow up 4.11(2.662,11.172), mothers delivered at health institution 4.07(2.992,10.722), and mothers counseled during antenatal care 1.96(1.124,4.732) had a positive association, while mothers with unable to read and write educational status 0.11(0.068,0.992) and employed mothers 0.22(0.169,0.561) were the variable that had a negative association with exclusive breastfeeding practice.Conclusion The prevalence of exclusive breastfeeding practice was relatively good. Marital status, educational status, occupation, antenatal care service, place of birth, and counseling of mothers during ANC were the independent predictors of exclusive breastfeeding practice.