We came across an unusual case of a 20 years old male from north India who presented with repeated episodes of pyrexia of unknown origin (PUO) and history of chronic hemolytic anemia. On investigation he was detected to have Sickle-β(+) Thalassemia and subtle features of hyposplenism. Radiological investigations revealed extensive splenic calcification and bone marrow examination to evaluate for PUO showed extensive bone marrow infarction and fibrosis. Molecular diagnosis for beta thalassemia mutation revealed heterozygosity for IVS 1-5 M and alpha globin genes were normal. This case highlights the wide variation of clinical phenotype which is encountered with Sickle-β(+) Thalassemia where genotyping can predict the clinical phenotype only partially.