Observations in laboratory cages showed importance of mating in the pattern of activities in the tomato fruit fly, Neoceratitis cyanescens (Bezzi) (Diptera: Tephritidae), in terms of frequency and allotted time within the daily organisation. Mating activities of flies were initiated in the early morning and lasted until early afternoon. The mean percentage of daily mating females and the mean duration of mating reached 88 + or -5% and 04.52 + or -1.23 h respectively. Egg-laying activities occurred mainly in the late afternoon. However, in the absence of male, the percentage of females that laid eggs did not vary significantly according to the time of the day. On the other hand, when males were introduced into the cage at midday, mating activities again predominated. In field cage or in the field, mating activities followed a similar pattern and occurred prefeentially on non host plants, although some males were sighted on host fruits in the morning, probably waiting for females. No male aggregation was observed. Further observations in an olfactometer (Katsoyannos et al, 1980) were performed to look at female attraction to male odor. Courtship pattern in this species appeared to be rather simple compared to other reported tephritids.