Objective: To compare the oral health status in two groups of oncohematological patients in a reference hospital in the south of Brazil.Methods: A retrospective cohort analytical study based on medical records review of adult's in patients with onco-hematological diseases followedup from April/2013 to April/2015. For data inclusion criteria it was considered in patients with onco-hematological disease, considering the death cases. Exclusion data criteria were absence or questionable information on medical records, inaccessibility of medical records as well inconsistency between information described by nursing team, medical team, dental team and others. The inpatients were divided into two groups: (A) without dental supportive care-considering inpatients with onco-hematological diseases who received dental assistance only in emergency cases; (B) with dental supportive care-considering inpatients with onco-hematological disease who received dental assistance regularly during hospitalization. The data collection consisted of gender, onco-hematological malignancies, presence of oral complications related to chemotherapy, and dental emergency during the hospitalization period. A descriptive analysis, Qui 2 and Fischer Tests were performed.Results: A total of 114 inpatients were enrolled, 55 (48.2%) on Group A and 59 (51.7%) on Group B. There was a male predominance in the sample (n=65). The Acute Myeloid Leukemia (17.5%) and Non-Hodgkin's Lymphoma (13.1%) were the major oncohematological malignancies diagnosed. Oral candidiasis was the major complication related to chemotherapy treatment in both groups. There was an association between regular dental supportive care and the diagnosis of oral complications due chemotherapy treatment (p<0.001). Conclusions:The presence of the dentists in the hospital environment has led to enhanced diagnostic accuracy in our sample, contributing to the improvement of the quality of life of inpatients. Further researches on this nature are important to augment performance of dental practice in the hospital setting.