As one of the leading causes of worldwide death, cancer accountsfor the majority of mortality rate annually. Despite stateof-the-art and highly-efficient diagnostic/therapeutic approaches,clinical manifestations in patients with cancer have not beencompletely reversed, yet, and patients with leukemia are notexceptions. According to the results acquired from a wide rangeof cell-based studies, a comprehensive understanding on thecellular and biological activities of genetically-manipulatedcells like Chimeric Antigen Receptor (CAR) T cells is essentialfor reaching our goals for the most appropriate treatment for patients with leukemia with fewer side effects.Data for this review article were collected from ۴۵ published articlesin the Full-text/full-length forms (original, review, RCTs,and case reports/series studies) obtained from Cochrane, ScienceDirect, PubMed, Scopus, Elsevier, and Google Scholarfrom ۲۰۲۰ to April ۲۰۲۳ using five keywords in English language.Studies with irrelevant/insufficient/data, or undefinedpractical methods were excluded.It has been demonstrated that CAR T cells seem to be as effectivetools for diagnosis, prognosis, treatment, and predictionor monitoring of leukemia. Results of a wide array of studiesproved that CAR T cells can be immuno-therapeutically usedfor identification of cancerous cells, tumor immunobiology,recognition of incorrect differentiation in the hematopoieticstem cells, and metastasis in patients with leukemia. This method,targeting a specific tumor antigen (CD۱۹), can be used inpersonalized oncology and drug delivery through the geneticmodification of T cells, which increases the anti-tumor propertiesof these cells for ۶ to ۱۲ months. Further investigationsand more collaboration among oncologists and immunologistsis highly recommended for following up the side effects likecentral nervous system toxicity, B cell aplasia, and cytokine secretionsyndrome in patients with leukemia.Results of our study provide CAR T cells a biological tool fora better prognostication and patient stratification aimed at improvingclinical outcomes in precision oncology for patientswith leukemia.