Objective: A complete blood count (CBC) analysis is an essential laboratory test for the diagnosis, treatment, and follow-up of numerous health problems. The aim of this study was to evaluate the reference intervals for CBC parameters of hemoglobin (Hb), hematocrit (Hct), white blood cell (WBC), platelet (Plt), and mean platelet volume (MPV) for the adult population in the Çukurova district of southern Türkiye. Materials and Methods: Data of 117,759 donors (112,557 males) 18–65 years of age who presented at the Çukurova University Blood Center between January 2015 and June 2020 for blood donation were included in the analyses. All of those who met the World Health Organization blood donor criteria were included in the study. Hematological reference intervals, stratified by age and gender, were compared. Results: The mean age of the donors was 37±9.8 years. The median parameter value was Hb: 15.4 g/dL, Hct: 46, WBC: 7.1x103/μL, Plt: 238x103/μL, and MPV: 8.3 fL. Comparison of the parameters between sexes revealed that Hb (p<0.001) and Hct (p<0.001) levels were significantly higher in males, while WBC and Plt counts were significantly higher in females (p<0.001 for each). The MPV values were similar. Conclusion: The reference ranges for CBC parameters as evaluated by sex and age group were clinically reasonable and in accordance with the literature data. However, given the single-center design of this study, additional studies with greater detail are needed to more fully assess the reference intervals of the general population in the region.