Hemoglobin (Hb) gene disorders are one of the most common inherited diseases in Taiwan, which include α-thalassemia, β-thalassemia, and Hb variants. In this study, we collected and analyzed mutations found in 930 patients with Hb gene disorders except Hb Bart’s Hydrops and β-thalassemia major. The patients included 650 cases of α-thalassemia, 225 cases of β-thalassemia, 9 cases of α-thalassemia combined with β-thalassemia, and 46 cases of Hb variants or Hb variants combined with α-thalassemia or β-thalassemia. The most common type of α0-thalassemia and α++-thalassemia mutations in our study were the SEA type deletion and the α3.7 deletion, respectively; the most common β-thalassemia mutation was the IVS-2 nt 654 C→T mutation; and the most common Hb variant was the HbE. We compared the relationships between genotype and hematological phenotypes of various Hb gene disorders and found that different genotypes of α0-thalassemia have similar hematological features. In conclusion, the results of our study provide data of the complex interaction of thalassemias and Hb variants which might be useful for other researchers in this field.