BackgroundNon-exclusive breastfeeding is becoming major cause of infants and children morbidity and mortality in developing countries including Ethiopia. The magnitude of non-exclusive breast feeding and its factors is not addressed in the study area.ObjectiveTo assess the prevalence of non-exclusive breast feeding and its factors in the first 6 months life of infants among mother-infant pairs of 6 to 12 months in Debre Tabor Town, Northwest Ethiopia, 2019.MethodsA Community based cross sectional study was conducted among 860 mother-infant pairs of 6 to 12 months in Debre Tabor Town, from March 1-30/2019. To select study participants cluster sampling technique was employed. Data was entered into Epi info version 7.2.0.1, and exported to SPSS window version 20 for analysis. Binary and Multivariable logistic regression was used to see the association between dependent and independent variables. Odds ratio with 95% confidence interval was computed. P-value < 0.05 was used to declare association.ResultsThe prevalence of non-exclusive breastfeeding of mothers to their infants within the first 6 months was found to be 39.8% (95% CI: 36.6-43.0). Mothers whose husbands had no formal education (AOR=6.60 [95%CI: 4.14, 10.41), primary education (AOR=4.30 [95% CI: 2.62, 7.20]), Mothers governmental employed ((AOR=8.20 [(95% CI: 5.191, 12.940]), daily laborer (AOR=1.70 [95% CI: 1.01, 2.90], merchant mothers (AOR=0.44 [95% CI: 0.35, 0.90]),and Mothers who had no post-natal care follow up for current baby in health service (AOR=2.40 [(95% CI: 1.56, 3.76]) were significantly associated with Non-exclusive breastfeeding within the first 6 months.Conclusion and RecommendationsHigh proportion of mothers practiced non-exclusive breast feeding within the first 6 months. Husband’s had no formal education, primary education maternal governmental employed, daily laborer, merchant and mothers who had no post-natal follow up were predictors with outcomes in the study area. Hence; it is better to increase annual leave for delivered mothers, improve awareness of husbands towards benefits of introducing complementary feeding timely, and advice mothers to improve post-natal period follow up.