Seven potato varieties were cultivated in 12 localities that can be classified into two characteristic regions: i) classical higher land region (cooler and more humid) and ii) lower land region (warmer and drier), in the years 1995-1997. Susceptibility to mechanical damage of the harvested tubers was studied extensively using the pendulum MIDAS 88 PP. The obtained parameter, so called ‘Pendulum index’ (PI), represents percent share of the tubers not damaged in the test. The obtained results show that season, region and variety significantly influence the pendulum index. PI of the tubers produced in the lower land region was significantly higher (~74%) in comparison to the higher land region (~61%). The season played the main role in the obtained PI values: 87% (1995), 53% (1996) and 64% (1997). The analysis of weather conditions shows that tuber susceptibility to mechanical damage is reduced by slightly higher than normal rainfall during the entire growing period. This relation becomes even more evident with rainfall at the end of the vegetation period (total rainfall in August and September of about 150 mm) and, at the same time, under slightly higher than normal temperature at the end of vegetation period. Weather variations and extremes have to lead to increasing potato damage.