In this research paper, we have explored effects of Jupiter (Guru) mahadasha on Lord Sri Rama according to the planetary positions in his birth chart ^[1-16] and ascertained its validity by comparing its results with Brihat Parashara Hora Shastra and Sage Valimiki’s Ramayana. We found that, Jupiter’s mahadasha remained 8 months 20 days only after his birth. This period entirely belonged to Rahu antardasha. As Jupiter (Guru) was exalted and placed in Cancer along with Moon in Lord Sri Rama’s birth chart, it has annulled all ill-effects of Rahu during his childhood.