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Morphological characters are not sufficient to properly identify different species of Trichoderma. Recently, multi-gene phylogeny in combination with morphological characters is used to identify Trichoderma at species level. The current study was focused to characterize Trichoderma asperellum strain Ta13 based on morphology and molecular analysis using genes such as ITS, tef1α, rpb2, act and cal. Light and scanning electron microscopy (SEM) results showed that Ta13 has regularly branched, typically paired conidiophores with straight phialides and globose to sub-globose shaped conidia having size of 2.91 µm x 2.37 µm with inconspicuous ornamentation. Sequence similarity analysis with reference T. asperellum isolates available in ISTH database showed 99.30, 90.60, 99.20, 98.70, 100 and 99.80 per cent nucleotide similarity for ITS1 and ITS2, tef1α intron4 (large), tef1α intron5 (short), rpb2, cal and act respectively. Confrontation assay clearly showed that Ta13 inhibited several fungal plant pathogens viz. Rhizoctonia solani (88.69 per cent), Fusarium oxysporum f. sp. lycopersici (85.27 per cent), F. moniliforme (84.55 per cent), S. sclerotiorum (80.17 per cent), S. rolfsii (78.26 per cent), and A. brassicicola (77.5 per cent).