Snap bean is economically paramount leguminous crops in Egypt. Increasing the productivity with high quality of snap bean pods is considered as substantial aim that could be achieved through using some plant-stimulants as foliar application due to their short stay in the soil. So this experiment was conducted to investigate the effect of some plant-stimulants, i.e., of algae (2 and 4 cm/L), potassium silicate (2 and 4 cm/L) nano chitosan (60 and 90 mg/L) and moringa extract (4 cm and 6/L) as a pre-harvest application compared with untreated plants (control) on vegetative growth parameters, chemical constituents of foliage, yield components and pod quality of snap bean plants (Phaseolus vulgaris L.) cv. Sybaris. Results indicated that snap bean plants given any of the pre-harvest treatments showed significantly higher values of all studied vegetative growth parameters (plant height, number of leaves/plant, leave area as well as fresh and dry weight), chemical constituents of snap bean plant foliage (N, P, K and total chlorophyll), pods chemical properties (TSS, total chlorophyll, total carbohydrate and protein contents), total yield and its components (number of pods/plant, early yield and total yield/fed. as well as marketable and unmarketable yield) compared with untreated plants (control). Results show clearly that most these parameters were significantly improved as a result of foliar application of either algae (2 and 4 cm/L) or potassium silicate (2 and 4 cm/L) at 21, 35, 50 days after sowing during the growing season compared with the control treatment.