The aim of this study was to investigate the microbiological quality of milk-shaked drinks including Bacillus cereus, Escherichia coli, Salmonella spp., Staphylococcus aureus, yeast and molds in unsealed containers sold in market fair, roadside and stall around Mahasarakham university. The analytical results revealed that microbiological quality of 30 samples of milk-shaked drinks in unsealed containers that did not pass the criteria of department of medicine, ministry of public health, Thailand were 50% of total samples. Bacteriological counts of Bacillus cereus, Escherichia coli, Salmonella spp. and Staphylococcus aureus of milk-based drinks that did not pass the criteria were 13.3, 10, 13.3 and 10% of total samples, respectively. Yeasts and molds counts of milk-based drinks that did not pass the criteria were 3.3 and 30% of total samples, respectively. Microbiological contamination of milk-shaked drinks was related to the hygiene of the shop and the supplier. It was found that the location of stall which high dust particles and animal carriers also contributed to the contamination of microorganisms. Moreover, the hygiene of the supplier may cause the milk-shaked drinks to be contaminated with microorganisms.