PERISCOPE project assesses factors promoting or preventing obesity development in early age. A specifi c aim is to assess preschool children ’ s physical activity habits in three different European countries. PERISCOPE has been implemented in 1094 children attending kindergartens in Denmark, Italy and Poland. The parents ’ and children ’ s physical activity habits and attitudes assessed by a questionnaire fi lled by the parents. Overweight and obesity assessed by Cole ’ s BMI cut-off points. Statistical analysis performed by χ^2 test and the test of proportion. Denmark shows the lowest rate (14.6 %) of overweight, followed by Poland (17.1%), while Italy shows the highest (21.2 %) (p < 0.0001). The Polish families show the highest rate of walking from home to kindergarten and back, followed by the Italians and, lastly, the Danish ones (p < 0.001). Almost all the Danish and Polish children, but only the 50.1 % of the Italians play outside (p < 0.001). During the weekdays, 34.9 % of Polish children, 22.2 % of Italians and 19.8 % of the Danish play outside more than one hour a day (p < 0.0001). During the weekend, 91.1 % of Polish children, 86.7 % of Danish children, but only 54.4 % of Italians play outside more than one hour (p < 0.0001). 53.5 % of Danish children, 31.9 % of Polish children, and 18.2 % of Italian ones practice sport (p < 0.0001). Danish children are the most active, the Polish are in the middle and the Italians are the least active. The difference in infrastructures (safety of walking streets, access to playgrounds/parks, etc.) can play an important role, in addition to cultural and social family characteristics, to the development of overweight.