Effect of temperament on milk yield, lactation length, physico-chemical properties and somatic cell count of Lacaune ewes were evaluated. The investigation was carried out at a sheep farm in the county of Győr-Moson-Sopron. The temperament of 106 Lacaune ewes was measured by the temperament 5-point-scale test (1=very nervous, 5=very quiet) during milking. Furthermore, 42 ewes were randomly selected from a herd of 106 animals for the analysis of milk composition (fat, protein and lactose), pH, electrical conductivity as well as somatic cell count. It was found that the temperament had a significant effect on lactation length and lactation milk production, lactose, electrical conductivity and somatic cell count. Calm ewes had significantly longer lactation (4 score: 220.7 day; 5 score: 201.4 day) as well as higher milk production (4 score: 207.9 kg; 5 score: 193.3 kg) compared to more temperamental animals (2+3 scores: 166.5 day and 135.5 kg; P<0.05). The content of lactose was significantly lower (4.32) in the more temperamental group, while electrical conductivity was higher (4.81 mS cm ). Additionally, significant differences were found in milk somatic cell count among the temperament categories. Calmer ewes had a lower somatic cell count in milk (5.17 log cm -3 ) than more temperamental ones (5.67 log cm -3 ; P<0.05).