Sustainable agriculture and food security could be affected by environmental factors, climate change and poor irrigation practices. Output and production of staple and economic crops are impacted negatively by environmental stressors brought about by extreme weather. Reports have been made of more than 6% of cultivable pieces of land contaminated by salt. High level of accumulation of dissolved salts can diminish growth in plants and crop yield. Emergence of nanoparticles has enhanced absorption of nutrients, improved photosynthesis and consequently improved crop production. This chapter looks at diverse factors that generate soil salinity, challenges on plants and its tolerance strategies; the recent advances in nanotechnology, nanofabrication, applications and impact in controlling saline stress in plants, such as: nanoparticles for nutrient delivery, water retention, antioxidant nanoparticles, smart nano-agri inputs and nanoparticle-enhanced photosynthesis.