Background/Objectives: Infant and young child feeding (IYCF) practices directly affect child health, development, and survival, especially under 2 years of age and ultimately affect adult life well-being. As the primary caregivers of the children, mothers with higher health literacy may better perceive the benefits of optimal complementary feeding practices, leading to improved health outcomes for their children. In this study, we aimed to assess complementary feeding practices among children aged 6–23 months in Turkey according to 2021 World Health Organization IYCF indicators [minimum dietary diversity (MDD); minimum meal frequency (MMF); minimum acceptable diet (MAD); egg and/or flesh food consumption (EFF); sweet beverage consumption (SwB); unhealthy food consumption (UFC); zero vegetable or fruit consumption (ZVF); and bottle feeding (BoF)] and investigate their associations with sociodemographic characteristics and mothers’ health literacy. Methods: With a descriptive study design, we reached 572 mothers of children aged 6–23 months from five regions of Turkey. We used the Turkey Health Literacy Scale-32 (TSOY-32) to assess mothers’ health literacy. Results: While maternal and child age are significantly associated with more complementary feeding practices, specifically MDD, MAD, and EFF, having multiple children has negative impacts on several complementary feeding indicators, including MDD, MMF, MAD, UFC, and ZVF. The only indicator associated with mothers’ TSOY-32 scores was zero fruit and vegetable consumption. Conclusion: Raising awareness among mothers about the importance of complementary feeding practices and identification of vulnerable groups will guide practitioners and policymakers to improve child health and nutrition.