The impact of zinc oxide nanoparticles (ZnONPs) on Triticum aestivum L. has been explored in this study. The wheat seedlings were allowed to grow on Hoagland and Knop agar medium supplemented with different concentrations of ZnONPs (2500, 5000, 7500, 10,000, and 15,000 ppm) for three weeks. To determine their effect, the growth parameters, viz., wheat seed germination, seedling growth, and chlorophyll content, were taken into consideration. Moreover, the bioaccumulation of ZnONPs in root cells was determined by means of SEM, and zinc content in ZnO NP treated seedlings was measured by ICP-MS. The abatement in seed germination was observed at all concentrations of ZnONPs used, except at 2500 ppm. The plant growth and chlorophyll content also declined with an increase in ZnONPs concentration, except at 2500 ppm. The maximum reduction in shoot height (23.7%), root length (66.8%), seedling fresh weight (33.8%), and dry weight (54.8%) was noticed at the highest concentration of ZnONPs (15,000 ppm). At 15,000 ppm of ZnONPs, the chlorophyll a, chlorophyll b, and total chlorophyll were reduced by 80.6%, 74.2%, and 78.5%, respectively. An elevation in Zn concentration was noticed with an increase in the concentration as revealed by the ICP-MS analysis. The TEM micrographs exhibit the accumulation of ZnONPs within the root cells of wheat seedlings treated with ZnONPs (15,000 ppm). Thus, nanoparticles may have a destructive effect on the plant, and therefore their considerate use is advisable. (c) 2022 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).