Huantai was the first county in northern China which achieved an average grain yield of 15 t/hm² from 1990, and has experienced a rapid agricultural intensification process since 1980s. Crop straw management has been an increasing challenge for local farmers and technicians as fuel demand decreased and uncoupling of animal husbandry with crop production. Huantai county initiated the program of crop straw incorporation to cropland since 1980s and by the 2010s, 100% of crop straw had been recycled. We collected crop production within the period of 1980-2014, and the corresponding parameters of straw and soil nutrients and soil organic carbon (SOC) contents, greenhouse gas (GHG) emissions and nitrogen (N) leaching, to quantify the ecological impacts of crop straw incorporation. The study found that crop straw incorporation contribution increased to 19.3%, 15.8% and 59.8% of N, phosphorous (P), and potassium (K) in total nutrients input (chemical fertilizer+straw) in 2014, respectively. In 2014, the SOC content (0-20 cm) for the whole county increased from 7.8±1.6 g/kg to 11.0±2.3 g/kg; meanwhile, soil available N, available P and available K increased by 134.0%, 138.5% and 62.2%, respectively, compared with that of 1982. During 2010s, global warming potential of N₂O, ammonia volatilization and N leaching were reduced at 24528 Mg CO₂-eq a^-1, 156.4 Mg N hm^-2 and 287.4 Mg N hm^-2, respectively. In the future, besides direct incorporation, other measures such as compost and replacement of animal husbandry feedstuffs, maybe introduced to further improve the economic and environmental benefits of straw incorporation.