Lameness in dairy cows represents one of the most serious animal welfare problems. Monitoring on-farm lameness prevalence is important for dairy producers and veterinarians in their efforts to reduce lameness. The aim of this study was to compare the prevalence of lame dairy cows assessed by locomotion score and estimated by farmers. For the onfarm lameness assessment a five point locomotion score was used. A number of 751 dairy cows were assessed in the cold season in 10 Transylvanian dairy farms. The results were statistically processed using the SPSS software, version 17. Out of 751 assessed cows 33.49% presented normal locomotion; 40.38% presented slight lameness; 18.03% were moderately lame; 5.17% were lame and 2.93% presented severe lameness. The prevalence of lameness established using the locomotion score varied from 4.76% to 68% (median 23.38%), and that estimated by the farmers ranged between 0 and 15% (median 7.50%). There were statistically significant differences (P<0.05) between the prevalence of lameness assessed using the locomotion score and that estimated by the farmers. It follows from the findings of this study that the dairy farmers are not aware about the locomotion problems of their cows.