The invention discloses a heptatomic condensed ring benzotriazole receptor micromolecule and a preparation method and application thereof. The compound takes heptatomic condensed ring benzotriazole (B) with an alkyl chain as intercalated nucleus, and cyan group as n-type fullerene receptor material (BIC) of an electrophilic unit. The preparation method comprises the following steps: by taking 4,7-dibromo-5,6-dinitro benzotriazole compound as a raw material, sequentially introducing thienothiophene with an alkyl chain by stille coupling reaction, then performing loop closing, introducing the alkyl chain to N by nucleophilic substitution, introducing aldehyde group via Vilsmeier-Haack, and then introducing a polar conjugation unit by Knoevenage reaction, so as to obtain a BIC compound; the micromolecule forms definite conformation and good solubility, has an electron receptor unit with universality, obtains a high efficiency (PCE of 13%) on a solar cell, and thus is a photovoltaic material full of potential.