The sustainability of agriculture relies on the development of strategies that lower the need for costly external inputs and minimize detrimental effects on the environment, which often involve either inappropriate or excessive use of agrochemical inputs. One strategy, integrating plant allelopathy into sustainable agriculture, is discussed in this paper. Agriculture integrated with allelopathy could reduce the heavy dependence on synthetic herbicides and other agrochemicals, and therefore ease problems such as environmental contamination, use of unsafe agricultural products and effects on human health. The allelopathy-integrated management of weeds includes various techniques such as the use of allelopathy in crop rotation, preceding and cover crops, green manure, mulch, and intercropping, as well as the incorporation of allelopathic plants in soil. In addition, the enhancement of weed-suppressing ability in crops is an important task in sustainable agricultural production. Even though many secondary metabolites involved in allelopathic activities have been isolated and identified, numerous allelochemicals remain unknown. The search for allelochemicals with novel modes of action is important for the development of bioactive pesticides. Despite the fact that the direct use of allelochemicals as natural pesticides is difficult in the field because of their easy degradation in nature and high cost of delivery, the synthesis of compounds derived from these allelochemicals may help resolve these problems.