Planted sweet pepper crop under greenhouse is subjected to salt stress which leads to a decline in overall performance of the crop. The purpose of these experiments was to see how Moringa oleifera leaf extract (1:30 v/v MLE to tap water) and salicylic acid (SA; 1mM) affected the growth, physiochemical attributes, and yields of sweet pepper (Capsicum annuum L.) plants grown in greenhouses with saline soil (EC= 2.41 dSm^-1 ) and irrigation water (EC= 2.01 dSm^-1  ). In sweet pepper plants, MLE or SA applied as a seedling spray or plant foliar spray improved growth characteristics (i.e., plant height, number and area of leaves per plant, and plant dry weight) as well as physiochemical attributes (i.e., total chlorophylls, total soluble sugars, free proline and ascorbic acid, and N, P, and K contents). In addition, early and total yields were improved when compared with the controls (seedlings and plant foliar spray with tap water). Combined treatments of MLE and SA (i.e., seedlings spray with MLE + plant foliar spray with MLE, seedlings spray with MLE + plant foliar spray with SA, seedlings spray with SA + plant foliar spray with MLE and seedlings spray with SA + plant foliar spray with SA) significantly increased all abovementioned parameters compared to the control. The combination of seedlings spray with MLE + plant foliar spray with MLE produced the most significant increase in total plant fruit weight over the control, with 39.4 % and 60.2 % in the first and second seasons, respectively. The combined treatment of seedlings spray with MLE + plant foliar spray with MLE then seedlings spray with MLE + plant foliar spray with SA gave the highest results of the growth and yields of sweet pepper plants by mitigation the injury of salinity stress (soil and irrigation water).