A series of three organic crystals were generated by slow evaporation solution technique from the organic compounds 4-Methylanilinium-4-hydroxybenzenesulfonate, 2-Amino-5-nitropyridinium trifluoroacetate and 2- Amino-4-methylpyridinium tartrate monohydrate. Their cytotoxic character was investigated by 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay method. These crystals in solution displayed potential cytotoxic activity.