Hematologists need four years of undergraduate studies, four years of medical school, one year internship, three years residency training in internal medicine and oncology and a further two to four years fellowship training in hematology/oncology.ematologist Salary. The average median hematologist salary in the United States is about $266,000 per year or about $128 per hour. The top 10th percentile of hematologists earn a salary of $412,000 or more per year which is about $198 or more per hour.