AIM: The aim of this study was to assess the impact of the presence of early childhood caries (ECC), traumatic dental injury (TDI), and malocclusion, as well as severe conditions, on the oral health-related quality of life (OHRQoL) of preschool children and families. MATERIALS AND METHODS: A cross-sectional survey was conducted in children aged 1 to 6 years old, who attended to the Department of Paediatric Dentistry, Gazi University. The questionnaires were adapted to Turkish, and OHRQoL was measured using the Turkish version of Early Childhood Oral Health Impact Scale (T-ECOHIS). Children were classified into four main groups, two subgroups in each group based on their severity conditions-Group 1: ECC group; Group 2: TDI group; Group 3: Malocclusion group; Group 4: Control group. Parents answered the questions about sociodemographic conditions and T-ECOHIS. The Kolmogorov-Smirnov test was used for non-normal distribution and Kruskal-Wallis and Mann-Whitney tests were used to compare T-ECOHIS score regarding ECC, TDI, and malocclusion. RESULTS: Both simple and severe conditions of TDI showed a negative impact on the family and child based on T-ECOHIS scores (P < 0.05). The severe condition of ECC and malocclusion showed significantly negative impact on family (P > 0.05) but not on child (P > 0.0.5). CONCLUSION: The presence of ECC, TDI, and malocclusion has a negative effect on OHRQoL of Turkish preschool children and specially their families. So, public health programs should be carried out about oral health for raising parents' and children's awareness and increasing OHRQoL.