The present study was conducted during two successive experimental seasons (2014 and 2015) on Fuerte avocado (Persea americana Mill.) at avocado orchard belonging to Horticulture Research Station at El-Kanater El-Khayira, Kalyubeia Governorate, Egypt. The trees were about 18-years old when this study started, planted at square system (7 meters apart), the soil orchard was clay loamy. The trees received the regular cultural treatments according the recommendation of Ministry of Agriculture and irrigated through farrow (surface) irrigation system. The objective of this study was to evaluate  the effect of (milagrow), nutrient compounds (potassium 10 %, phosphorus 20 %, boron 3 % and brassinolide 0.2 %), on fruit set and fruit retention (%), number of fruit/tree and yield as well as fruit quality of avocado tree cv. Fuerte. This study evaluated applications of milagrow 0 (control), 2.5, 5.0 and 7.5 g/L at different growth stages; a) swollen bud stage, b) Full bloom c) beginning of fruit set during 2014-2015. Results cleared that foliar applications of milagrow to avocado tree cv. Fuerte increased all fruit parameters. Regard to fruit set and fruit retention % trees which treated with 7.5 g/100 L produced the highest value of each. Regarding the yield, highest yield was obtained from treated with 5 g/100 L in comparison with other treatments followed by “7.5 g/100 L" and “2.5 g/100 L" while it was the lowest with "control". As well as trees which treated with 7.5g/100 L and 5 g/100 L produced the highest number of fruits /tree while the lowest number of fruits/tree was recorded for untreated trees. Concerning physical properties, data proved the highest value of  fruits in their weight, dimensions and flesh/fruit weight % with treatment 5 g/L meanwhile the lowest fruits were on the opposite at treatment 2.5g/L and untreated trees. Regarding fat content, the differences between treatments did not reach the level of significance. Results indicated that if milagrow is used at swollen bud stage as foliar application, increased both fruit yield and improved fruit quality. Additionally, milagrow resulted in yield increment.