THIS investigation was carried out in a private orchard belonging ……. to Mr. Husain Saber, located at El Kalubia governorate, Egypt, on Balady mandarin (citrus reticulata) trees budded on sour orange rootstock .Trees were under flood irrigation system, grown in a clay loamy soil. The investigation aimed to verify the response of Balady mandarin to compost, some biofertilizers and raw Natural Minerals Compound (N.M.C) in silicon represents the major component. The study contained 10 treatments (three levels of compost at 50, 75 and 100% of the amount of actual nitrogen required to mandarin tree, three levels of (N.M.C) at 4, 5 and 6 kg /tree/ year with some biofertilizers and control treatment (compost at 25% N + recommended mineral fertilizers). Trees were treated by all different treatments which used under study during three seasons, “on year" 2011, off year" 2012 “, and “on year" 2013, and data collection were done during two seasons on year “heavy load yield" (2011 and 2013). The obtained results cleared that, application of (50% compost + biofertilizer + 6 or 5 kg N.M.C) / tree / year was the best combination for resulting in maximum yield and improving fruit quality (increased fruit size, peel thickness, juice weight % , T.S.S/acid ratio , Vit.C and to decrease fruit acidity, fruit nitrite and nitrate contents ). Using the high level of compost decreased leaf mineral contents this may be attributed to the increase of soil salinity as a result of application of compost which it's high EC (3.73mmhos/cm). All treatments enhanced soil biological activity in terms of increasing the total count bacteria (Bacillus circulans, Bacillus megaterium and Azotobacter chroococcum) compared with control treatment. Based on the economic study it could be concluded that, there was an increase in the final cost of organic production as compared with the conventional production (control treatment), nevertheless, the price of organic farming production is usually much higher than the price of conventional fruit production because it has safety food and high fruit quality especially for