Background: Hematological derangements are among the common complications associated with HIV infection. HIV infection may affect any cell line causing, anemia, thrombocytopenia, and leucopenia or may cause pancytopenia. Patients and Materials: This study was conducted at Pakistan Institute of Medical Sciences, Islamabad from March 2017 to June 2017. Patients were diagnosed as HIV positive as per WHO criteria. Detailed medical history, physical examination, and investigations were conducted. Data was collected and analyzed on SPSS version 21.0. Results: Total 92 patients were selected for the study. Patients were divided into two groups. Group A consists of 48 control patients. Group B consists of 44 HIV – positive patients. Majority of patients belonged to reproductive age group (16 – 45 years) in both groups. Male to female ratio was higher (3:1) in both groups. Common clinical features among patients were fever (85%), weight loss (73%), anemia (35%) and oral thrush (19%) in Group B. Conclusion: Hematological abnormalities were present in presence of HIV infection as compared to control group. This may has significant effect on clinical outcome of the disease. So all the HIV- positive patients should be investigated for routine hematological evaluation.