The experiment was conducted to evaluate the effect of effective microorganisms (EM) containing Lactobacillus spp. on production performances of cross-bred Jersey cows in dry zone of Sri Lanka. Six, cross-bred (Jersey × Sahiwal) milking cows were randomly assigned to the control and treatment groups. Animals in treatment group were daily given with EM after the milking. Higher average milk volume was observed in animals provided with EM (P < 0.05). However, higher milk fat contents were observed in the control group (P < 0.05). Solid non-fat content in milk was not significantly different (P > 0.05) between control and treatment groups. Body condition score of animals in both groups were similar (P > 0.05). Further, less unpleasant odour and fewer amounts of undigested feed materials were observed in cow dung of animals provided with EM. Therefore, results revealed that supplementing Lactobacillus spp. increases the milk volume and improves health of Jersey × Sahiwal cross-bred dairy cows, reduces cost of production and controlled malodor in the farms. The economic analysis for using EM in dairy cows indicates that EM is a cheaper product and could be used profitably in dairy farming.