Introduction of complementary foods to infants is a common practice. However, according to recommended infant and young child feeding protocol the timing of introduction, frequency of feeding and the quality of diet are not appropriate. Thus, the aim of this study is to determine the magnitude and identify the predictors of appropriate complementary feeding practice among mothers of children 6-23 months of age in Kedida Gamela district, southern Ethiopia. A community based cross sectional study was conducted among mothers of children aged 6-23 months on March 2017. A total of 777 randomly selected mothers/caregivers paired with their children aged 6-23 months were interviewed by trained nurses. Data were entered, cleaned and analyzed by using SPSS version 20. Descriptive analyses were done for main variables. Exposures with p-value less than 0.25 on bivariate analysis were taken for multivariate analysis. Statistical significance was declared at p<0.05 and adjusted odds ratio (AOR) with 95% confidence interval (CI) was reported. The proportion of appropriate complementary feeding was 21% in the study area. Maternal age 18-24 years [AOR=4.01,95% CI (1.78, 9.04)], mothers with children 6-11 months of age [AOR=2.88, 95% CI (1.68, 4.94)] and 12-23 months of age [AOR=2.67, 95% CI (1.61, 4.45)], mothers who attended postnatal care follow up [AOR=2.14, 95% CI (1.14, 4.02)], and living in a food secure household [AOR=2.23, 95% CI (1.30, 3.82)] were the factors associated with appropriate complementary feeding practice. Mothers in the age range of 18-24 years, mothers having children of 6-11 months and 12-23 months of age, attending postnatal care follow up and living in a food secure household were the predictors of appropriate complementary feeding practice. Mothers should be encouraged to attend postnatal care follow up and income generating activity should be made to assure household food security status to prevent economical vulnerability of households.