Background: Leukemia is one of the most occurring haematological pathologies in the world which develops due to the impairment in the hematopoietic machinery. Cellular death via apoptosis is severely impaired in this pathophysiological condition and leads to the progression of the disease. Objective: We have tried to unearth the efficacy of Withanolide D, a steroidal lactone derived from Withania somnifera or Ashwagandha on some of the apoptotic machinery components, i.e. TERT, BCL2 and PUMA in the experimental leukemic mice. Materials and Methods: LD50 and EC50 values of Withanolide D were estimated. Three groups of animals were taken for experimental purpose i.e. Group I = Leukemic, (L); Group II = Control, (C); Group III = Leukemic treated with Withanolide D, (L + WD). Group III received Withanolide D via oral route and other two groups received equal volume of distilled water. Various cytological, immunofluorescence and flow cytometric studies were taken into consideration post administration. Result: Leukemic group showed increased cellular proliferation and decreased cellular death as compared to control. Post Withanolide D administration TERT, BCL2 and PUMA expression started to shift towards normal status. This shift in the expressional values of increased apoptosis rate and decreased cellular proliferation revealed by cytological, immunofluorescence studies and flow cytometric investigations. Conclusion: As Withanolide D decreased the suppression of apoptosis and impaired the progression of the disease, so, we can conclude that Withanolide D of Ashwagandha may hold a promise towards a new therapeutic strategy in leukemia.