Heavy metal pollution is a widespread issue that directly threatens global food security. An experiment was carried out on wheat (Triticum asetivum L.) to assess the toxic effects of Pb or Ni stress and the role of Sonchus oleraceus (S) extract as a grain priming application in ameliorating the stress effects. The data showed that 100 mM Pb or Ni stress significantly reduced wheat plant growth parameters, total soluble carbohydrates (TSC), total amino acids and minerals content; while the levels of total soluble proteins (TSP) and the contents of Pb or Ni ions in the root and shoot tissues were significantly increased. The priming with S extract restored most of the metabolic activities, improving growth criteria, TSC and mineral levels. Surprisingly, priming with S extract reduced heavy metal accumulation in wheat root and shoot tissues. In a conclusion, using natural S extract as a simple priming application could be presented as a long-term, and a risk-free method for mitigating the negative effects of Pb or Ni stress on wheat.