This investigation was carried out during the two successive seasons of (2013 and 2014) on 20-years-old Washington Navel orange (Citrus sinensis L. Osbeck) trees budded on sour orange (Citrus aurantium L.) rootstock grown in clay soil in a private orchard at Kafr El-Dawar region, EL-Behira Governorate, Egypt,  to improve mineral contents, yield and fruit quality by pre-harvest foliar applications with Putrescine at (2, 4 and 6 mM), Spermine at (2, 4 and 6 mM), Jasmine Oil at (0.04, 0.06 and 0.08 %),  Thyme Oil at (0.04, 0.06 and 0.08 %),  Garlic Extract at (1, 1.5 and 2 %), Clove Extract at (1, 1.5 and 2 %), Algaefol Extract at (1, 1.5 and 2 %), Jisamar Extract at (1, 1.5 and 2 %) and control (untreated trees).
Four foliar spraying were carried on trees from each treatment as follows, the first application was just at full bloom for Washington Navel orange trees. The second application was after 30 days from the first one, the third application was after 30 days from the second and the fourth application was before 45 days from the harvest date. The obtained results revealed that all foliar applications improved leaf mineral contents and increased yield as (number of fruits and weight kg per tree), average fruit weight compared with control, while it clearly decreased pre-harvest fruit drop during two seasons. Moreover, it improved TSS, acidity, vitamin C, TSS/Acid ratio, total sugars, reducing sugars and non-reducing sugars contents compared with the control. In addition, the two higher concentrations of all treatments were more effective than the low concentration on improving yield, mineral content and fruit quality of Washington Navel orange fruits.