Compared to the queen or the workers, the biology of honey bee Apis mellifera L. drones is poorly known. Available information on drone activity is based mainly on direct observations during a limited period of time and for a restricted time of the day. Complete registers of the flight activity of honey bee drones are lacking. We studied the activity of A. mellifera drones during their entire life in spring and summer by using an optical bee counter at the entrance of the hive. Drones were active in the afternoon, with most flights occurring between 14:00 and 18:00. Short orientation flights were performed at 6–9 days old, and longer mating flights of 30 min were performed from the age of 21 days onward during the spring and from the age of 13 days onward during the summer. Our registers show that 50 and 80% of the drones remained faithful to their colony (did not drift) in spring and summer, respectively. The present study confirms existing information, but also reveals unknown aspects about drone biology.