The invention belongs to the fields of the pharmaceuticals and the chemical engineering, and relates to bicyclic-substituted pyrazolone azo compounds, and a preparation method and a use thereof, and concretely relates to compounds represented by formula I, or pharmaceutically acceptable salts or solvates thereof, wherein L and R1 to R6 are defined as in the specification and the claims. The invention also relates to a preparation method of the compounds of formula I, a medicinal composition of the compounds, and a medicinal use of the compounds. The compounds of formula are an effective TOP receptor stimulant, and are a good thrombocytopenia treatment drug.