Abstract The aim of this study was to investigate the occurrence, type and severity of anemia at the time of diagnosis of oral cancer, and its potential association with the degree of tumor cell differentiation. This case-control study used 366 medical records of patients treated at two referral centers for oral cancer diagnosis, specifically: cases (n=70) with a histopathological diagnosis of oral squamous cell carcinoma (OSCC) of the oral cavity, and controls (n=296) with benign oral lesions. Sociodemographic, behavioral, and clinical variables of both groups, as well as complete blood count values, were analyzed by descriptive statistics and crude/adjusted logistic regression. Anemia was detected in 15.7% of the cases and 11.8% of the controls. The presence of anemia had an OR=1.64 (odds ratio) (95%CI 0.54–5.00) for OSCC, with no significantly statistical association. Normocytic anemia was the most prevalent form of anemia when oral cancer was diagnosed (91.4% of the controls and 72.7% of the cases), and moderate to severely low hemoglobin levels were associated with OSCC diagnosis (OR 6.49; 95%CI 1.18–35.24), albeit data on hematological examinations were missing.