The comprehensive utilizations of discarded tobacco leaves are discussed, from which different products such as nicotine,solanesol,amino acid,organic acids,organic fertilizer and activated carbon can be gotten. In extracting,purifi-cating and measuring useful composition of different kinds from tobacco leaves, their properties, especially the stability of solanesol in the sunlight and different solvents have been further research. Comparing and summing up the methods of nicotine, solanesol and their properties and utilizations, as well as the comprehensive utilizations at home and abroad, it helps to make good use of tobacco waste and obtain more tobacco leaves products of high value.