Thirty-two genotypes of greengram were examined for their tolerance to aluminium (Al) toxicity using the growth response and haematoxylin staining techniques. Root staining score, post-staining root regrowth, and root and shoot length were the main characteristics to determine Al toxicity tolerance. With the exception of the root staining score, there was significant variation in the greengram genotypes' tolerance to Al toxicity. During screening with varied concentrations of Al, the amount of 150 µM Al produced the best discrimination power between the genotypes of greengram. Based on the score, genotypes could not be distinguished well using root staining. On the other hand, greengram genotypes for aluminium tolerance at the seedling stage were distinguished by the root regrowth that occurred after staining. When exposed to 150 µM aluminium concentration, the genotypes Pusa 1031, Pusa Ratna, and MH-421 showed long root regeneration (1.38, 1.20, and 1.10 cm, respectively), whereas Meha and Pusa 1431 showed short root regrowth (0.16 and 0.13 cm, respectively). Additionally, this study demonstrated that greengram Al tolerance is constant throughout the plant growth stage, allowing selection for enhanced Al tolerance to occur during the seedling growth stage. Genotypes Pusa 1031 and P 672 had shown highest P content (4.53% and 4.37 %) and PUE (254 % and 245%) under control conditions and under Al toxic conditions, genotypes HUM-16 and Pusa Ratna had shown highest P% (2.17 and 2.15) and PUE (121 % and 120%). This study revealed that different genotypes of greengram had different potential to perform differently under Al toxicity condition in acidic soils.