Colocasia esculenta (L.) Schott, a commonly growing plant in industrial effluent affected areas, was selected for observation of the effects of industrial effluents on chromosomal and DNA levels. Five different industries—(i) Textile (ii) Pesticide (iii) Tannery (iv) Ceramic and (v) Pharmaceutical—in and around Dhaka City were selected for this study. The diploid chromosome number 2n=28 was found in the specimens collected from textile, pesticide and tannery effluent-affected areas similar to the control. However, 2n=38 were observed in the plant sample collected from Ceramic and Pharmaceutical areas. The probable reason for increasing chromosome number was non-disjunction of certain chromosomes at anaphase due to inhibition of spindle formation. The fluorescent karyotypes of the plant showed significant differences between the samples and the control. Fluorescent banding (CMA and DAPI) revealed the occurrence of probable genomic reshuffling by deletion and tandem duplication. The different plant samples of the species had characteristics RAPD fingerprinting. Lacking of some DNA fragments in some sample plants may correlate to the deletion of chromosomal parts. Similarly, some new fragments in the sample plants may correspond with the tandem duplication of the chromosomal part. Therefore, the substances present in the industrial effluents affected on the chromosome and DNA level of Colocasia esculenta.