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Plastics, being xenobiotics, accumulate and cause deleterious effect on the environment. Fungi that could degrade polyester polyurethane (PU), a polymer plastic component, were screened using the halo zone assay. Four of 18 test fungi exhibited potential for degrading PU. Crystal-like structures were formed in the culture medium where PU degradation was observed. This is the first report on the formation of such structure associated with plastic degradation. Pairwise test showed that the biomass dry weights produced by potential PU degraders in liquid culture medium with PU and in potato dextrose broth (PDB) were not significantly different, suggesting that the isolates can actively grow using PU as main carbon source. The four isolates could also grow in nitrogen-free mineral medium with PU as substrate, suggesting that PU can also be utilized as source of nitrogen for growth. Analysis of the sequence of the internal transcribed spacer region between the 18S and 28S ribosomal nuclear RNA genes identified the isolates FI0101, FI0602 and FI1803 as Lasiodiplodia theobromae, Penicillium janthinellum and Fusarium verticillioides, respectively. FI1503 was identified as Paecilomyces puntonii based on phenotypic characteristics. Results may provide prospects for future biodegradation studies of plastic materials.