Abstract: Ayurveda is a science of life that emphasizes prevention and health promotion. its main objective is to gain optimal health and give strength to fight against diseases. The physiological, anatomical, and pathological entities described in Ayurveda have a variety of features that help with conceptual understanding. According to Ayurveda Ojas is the essence of all the rasa-raktadi seven dhatus also considered the best support of life. In shusruta samhita ojas mentioned as Bala. Bala plays an important role in nidana and chikitsa of diseases. Bala and immunity are interrelated, Ayurvedic literature is evident based on science, and it is evident that bala is involved in sadhyasadhyata. nidan panchak, arishta lakshana etc  It also plays an important role to choice line of treatment. The presence review explore more about concept of ojas and bala.

Key words:  Bala, Ojas , strength, Dhatusara