Anthracnose of banana was caused by Colletotrichum musae (Berk.& Curt.) Arx. It could infect bananas as latent infection from the field. Bananas from Nonthaburi, Nakorn Pathom, Ratchaburi, Pathumthani had percentages of infection at 87.2, 83.0, 78.0 and 77.0 at ripening stage. Fungal isolates from these areas had similarity morphological characteristics and growth rate on potato dextrose agar (PDA). Optimal growth and sporulation of this fungus was obtained on PDA, pH 4-7, 25-30 degree C under alternate lighting 12 hrs. fluorescens/12 hrs. dark. Infected green fruits showed the symptom as fruits started to ripe (stage 4) with total soluble solids (TSS) 18 % Brix. The lesions increased in size as ripening progress. Diseased fruits had higher respiration and ethylene production rate than healthy fruits. The efficacy of thiabendazole, benomyl, thiophanate-methyl prochloraz, imazalil in controlling this disease were conducted. Dipping bananas in imazalil at concentration of 250 ppm for 3 mins was the most effective method. The treated bananas could be kept in cold storage at 15 degree C for 30 days without changes in color, firmness and disease symptom. After ripening these bananas at room temperature, they could ripe normally without disease symptoms. Bananas dipped in imazalil at 250 ppm for 3 mins were analysed for imazalil residues by using bioassay method. One hour after dipping, the outer portion of peel of bananas contained 44 ppm of imazalil. After 20 hrs, the residue reduced to 12 and 13 ppm in the outer and inner of the peel respectively.