Аннотация:A morningness-eveningness questionnaire was administered to 34 golfers and 23 waterpolo-players to assess the influence of diurnal individual differences on the athletic performance levels. No differences in the diurnal type (“morning” vs “evening” individuals) were found among low-performing athletes, while in the high-performing group golfers had higher morningness scores than the waterpolo-players. The results suggest a relation between the diurnal type, performance level, and the time of day when the match is played (morning for golf and evening for waterpolo).