Background: Gestational trophoblastic disease (GTD) is an uncommon complication of pregnancy, worldwide the incidence varying between 0.5 & 0.8 cases per 1000 live births. β-hCG has been used as standard tool for monitoring the biological activity of trophoblastic diseases and as a tumour marker. The abundant vascular supply of the tumour makes Colour Doppler Ultrasound a potentially useful tool to study its clinical behaviour. Objective: To evaluate the role of uterine artery doppler in earlier prediction of resolution in post molar surveillance compared to serial β-hCG follow up. Methods: A longitudinal prospective cohort study was conducted in Government Rajaji Hospital, Madurai over a period of 12 months from August 2015 to August 2016.40 cases of vesicular molewere studied andassessed before and after suction evacuation by measuring serum β-hCG level and finding its relation with Uterine ArteryResistance Index (RI). Results: Out of the forty patients,36 patients showed resolution of mole characterised by fall in b-hcg values and rise in U/A RI while 4 patients showed progression to invasive mole characterised by plateauing or rise in b-hcg values and a fall in U/A RI in the post evacuation period compared to pre evacuation values.Based on these observations,patients were grouped as molar pregnancy resolution(↑UARI with ↓ẞHCG – 90.00%) and molar pregnancy progression(↓UARI with ↑ or plateau ẞHCG – 90.00% ) groups showing a statistically significant differencewith a p value of <0.05 implying that variation in UARI measurement in relation to ẞHCG levels correlate strongly, inversely and negatively. Conclusion: Finding such a significant correlation between serum β-hCG level and Doppler indices suggest that uterine artery Doppler may be used to predict the course of the disease much earlier than serial follow up with B-hcg.