Current environmental conditions have prompted agri-food systems to explore new strategies for improving the production of crops in a sustainable manner. The use of omeprazole (OMP) and melatonin (MEL) have been proposed as innovative strategy for crop improvement when applied as biostimulants. However, although their role in the growth of several species has been studied, the results in photosynthetic efficiency parameters are still scarce. Therefore, the objec-tive of the present study was to evaluate the effect of foliar application of OMP and MEL on bi-omass, yield, SPAD values, leaf chlorophyll fluorescence (Fv/Fm), photochemical quenching (qP), Non-photochemical quenching (NPQ), quantum yield of photosystem II (PhiPSII) and elec-tron transport rate (ETR) in bean plants. Treatments were applied separately at doses of 1, 10, and 100 µM, plus a control without application. The results obtained indicate that OMP and MEL were able to increase biomass, yield, SPAD values, as well as photochemical quenching, fluores-cence, and PhiPSII coefficients. Finally, it is concluded that foliar application of OMP and MEL at a dose of 1 and 10 µM can increase photosynthetic efficiency and decrease photoinhibition, which is reflected in higher biomass accumulation and yield in green bean plants cv. Strike.