The aim of study was to evaluate teat traumatization caused by two milking system (CMS – conventional milking system, AMS – automatic milking system). IRT method was used for the evaluation. The stables with AMS and CMS (tandem milking parlour) were included in the monitoring. The vacuum level was 42 kPa in both systems. Teat surface temperature was measured immediately before and after milking. The study showed that AMS had caused an insignificant increase of the teat temperature during milking compared to CMS. IRT can be recommended as a method that can produce important information about milking process.