The Mediterranean region, where olive trees are cultivated, is known to have hot and dry summers with high irradiance level and low precipitation. It is known that olive trees are well adapted to hot and dry conditions; however heat stress and intense solar radiation can affect fruit and oil production, in terms of quantity and quality. In the present study, fruit samples of three olive cultivars: ‘Maraki’, ‘Dolce’ and ‘Manzanillo’ grown in south Egypt, Qena governorate, were harvested to monitor the characteristics of the fruit and the quality of the oil in response to different environmental factors. Results indicated that high temperature, high irradiance, and low rainfall rate during fruit growth period have fairly affected fruit development. Fruit weight, size and flesh/stone ratio were slightly lower than the typical range of the three cultivars, while oil and moisture contents were within the range. The fatty acids profile of the oil has changed due to the reduction in the percentage of some saturated fatty acids, and the increase in the percentage of unsaturated fatty acids. The spectrometric indices were increased, whereas the physiochemical and antioxidant properties of the oil, such as total polyphenolic compounds, acid value, iodine value, tocopherol and chlorophyll contents stayed within the limits of the extra virgin oil of the cultivars. Results indicated that fruit from the three olive cultivars maintained good fruit characteristics and oil quality, suggesting that these fruit can be used for extra virgin oil production under the condition of south Egypt.