Abstract: Background and Objective: Allelochemicals extracted from plant either through leaf or root can affect growth and productivity of surrounding plants and crops. The purpose of this study was to determine the morphological, physiological and yield responses of finger millet growing near the mangrove Excoecaria agallocha L. in coastal areas. Materials and Methods: The study was conducted in the laboratory from November, 2016 to January, 2017 and used Randomized Block Design (RBD) with two factors, different concentrations (25, 50, 75 and 100% ) of leaf leachates of mangrove Excoecaria agallocha and two finger millet varieties (brown and white). Germination, shoot length, seedling dry matter, vigour index were recorded at 10 days after sowing in all the test crops. The photosynthetic pigments, soluble proteins, osmolyte proline and phenol content were also estimated. Further gas chromatographic analysis was also done for the identification of allelochemicals. Correlation coefficient was determined by plotting data from all treatments and the relation amongst seedling growth parameters and seedling vigour index was examined. Significance between control and treatment was compared at 0.05 probability level. Results: Results showed that E. agallocha leaf leachate extracts have significant effect (p<0.001) on the entire seedling growth and highest inhibition was observed at 75 and 100% concentration. The correlation study revealed that the vigour index was significantly correlated with shoot length (p<0.05) and dry matter (p<0.01) for 100% leaf litter leachate concentration Conclusion: It is concluded that the inhibitory effect of the test species on seed germination and seedlings of finger millet cultivars may be related to the presence of allelochemicals including fatty acids, flavonoids and phenolic acids.