During the entire period of internode growth of Merremia emarginata contents of gibberellic acid (GA3), phenyl-acetic acid (PAA), indole-3-acetic acid (IAA, free and conjugated) and abscisic acid (ABA, free and conjugated) were estimated by ELISA using polyclonal antibodies raised against each hormones. At the time of internode elongation free auxin content was low and increased with the decrease in the rate of elongation. In contrast, conjugated IAA showed declining trend where free IAA content was remarkably high, suggesting thereby that conjugated IAA might have mobilized during the later phase of internode development. The endogenous GA3 contents were high as compared to other hormones; however, no significant role of GA3 was discernible in elongation growth. Conjugated ABA contents remained very low during the elongation growth and increased thereafter.