Early diagnosis and cure for patients with chronic myeloid leukemia (CML) exhibit significant clinical challenges because of the disease progression from chronic phase (CP) into a rapidly fatal blast crisis. Our earlier studies suggested an association of sperm associated antigen 9 (SPAG9) with various human malignancies. The present investigation revealed that SPAG9 mRNA and protein are expressed in CML patients (88%), in K562 and KCL-22 cells. Further, SPAG9 protein expression was also detected on cell surface suggesting that this molecule may be a suitable target for immunotherapy. Interestingly, 90% CML-CP patients showed humoral response against SPAG9, suggesting its important role in early diagnostic of CML-CP. Further investigation is warranted in establishing the potential of SPAG9 as a biomarker and immunotherapeutic target for early treatment of CML-CP patients.