The domestic population of walnut ( Juglans regia L.) in Serbia is highly heterogeneous as a result of many centuries of propagation from seed. This paper describes variation observed in this population over the past four decades. The date of budbreak showed a 50-day range, and the date of leaf drop a 32-day range. Average nut weight ranged from 3.3 g to 29.0 g and the kernel percentage from 26.2% to 64.3%. The number of female flowers per inflorescence ranged from 1 to 32 and the number of nuts per cluster from 1 to 15.