Objective: To analyze the hematological characteristics of a patient with Hb Ottawa in conjunction with β-thalassemia. Methods: Peripheral blood samples from the proband and her parents were collected and subjected to red blood cell analysis and hemoglobin electrophoresis. Genotypes of α- and β-globin genes were also analyzed. Results: The proband and her mother were both heterozygotes for Hb Ottawa and β-thalassemia variant IVS II-654, and presented with typical β-thalassemia trait featuring hypochromic microcytic anemia. An abnormal hemoglobin band was detected upon electrophoresis. Conclusion Co-existence of Hb Ottawa and β-thalassemia may not aggravate the phenotype.