The most common fungal pathogens are found in the Colletotrichum genus, which causes economically significant anthracnose or blight disease in various tropical and subtropical fruits and vegetables. Despite that, the excessive application of chemical pesticides in agriculture has caused many problems, such as poor soil fertility, pollution, and risk to human health due to the toxic accumulation of pesticides in the soil. This study was carried out to isolate potential bacterial colonies from five different soil sources around Universiti Malaysia Terengganu (UMT) and to screen the isolated bacteria for antagonistic effects against Colletotrichum species. In total, 50 bacterial strains were isolated and subjected to selective screening to distinguish bacterial strains capable of inhibiting Colletotrichum sp. Based on the selective screening, nine bacterial strains with different morphology were selected and tested further in quantitative screening by calculating their Percentage of Inhibition of Radial Growth (PIRG). The results showed that S5-H strain demonstrated the highest inhibitory effect at (75.67 ± 2.86)%, followed by S5-I strain (68.89 ± 5.93)%, S5-D strain (66.89 ± 6.15)%, S3-C strain (60.33 ± 3.19)%, S5-F strain (57.89 ± 4.66)%, S5-G strain (53 ± 5.79)%, S2-I strain (41.33 ± 7.26)%, S4-B strain (40 ± 7.07)%, and S3-D strain (38.33 ± 8.90)%. Based on the results, bacterial isolate S5-H with yellow, round, convex, and entire colony from mangrove muddy sediment was shown to have the potential to be utilised as biopesticides against Colletotrichum sp. Nevertheless, this study requires further work in the future, focusing on species identification by 16S rRNA phylogeny and the mechanism of action exhibited by the S5-H strain.