The present study was carried out to investigate the beneficial and toxicological effect of plant-based titanium dioxide nanoparticles (TiO2 NPs) on the morphophysiological attributes of wheat plants under salinity stress. The biogenesis of titanium dioxide nanoparticles was accomplished by using the extract of Buddleja asiatica L. leaves followed by characterization through UV visible spectroscopy, SEM, FTIR, and EDX. NaCl salt was applied in two different concentrations after 21 days of germination followed by foliar applications of various concentrations of TiO2 NPs (20, 40, 60, 80 mg/L) to salinity-tolerant (Faisalabad-08) and salinity-susceptible (NARC-11) wheat varieties after 10–15 days of application of salt stress. Salinity stress showed remarkable decrease in morphophysiological attributes of selected wheat varieties. Magnificent improvement in plant height, dry and fresh weight of plants, shoot and root length, root and shoot fresh and dry weight, number of leaves per plant, RWC, MSI, chlorophyll a and b, and total chlorophyll contents has been observed when 40 mg/L of TiO2 NPs was used. However, the plant morphophysiological parameters decreased gradually at higher concentrations (60 and 80 mg/L) in both selected wheat varieties. Therefore, 40 mg/L concentration of TiO2 NPs was found most preferable to increase the growth agronomic and physiological attributes of selected wheat varieties under salinity.