Productivity, fruit setting, fruit drop, yield and fruit quality of Washington navel orange (Citrus sinensis L. Osbeck) trees in response to spraying both calcium chloride (CaCl2) at 0.5, 1.0, 1.5 and 2.0% and boric acid (H3BO3) at 0.050, 0.075, 0.1 % and 0.2% were evaluated during two successive seasons, 2014 and 2015 at El-Kanater El-Khayria research station, El-Qalyubeia Gov., Egypt. The experiment was designed as randomized complete block design with three replications. Results showed that most of boron treatments and the high concentrations of calcium applications were effective in improving the final fruit set %, yield (kg), fruit quality as well as average fruit weight, average fruit volume, TSS (%) and vitamin C as compared to the control. They also, led to significant decrease in June-drop (%) and juice acidity (%). However, the best results with regard to fruit setting, yield and fruit quality were significantly obtained due to spraying trees with 0.2% boric acid followed by 2.0% Calcium chloride treatments. So, we may recommend to apply both of these treatments to maximize the productivity and the upmost profits.