NOVELTY - Preparation of dispirofluorene-indenofluorene derivative (I) or (II) comprises heating 9-oxo-1,4-diphenyl fluoro-3-methylformate (III) to 118 degrees C to obtain 9-oxo-1,4-diphenyl fluoro-3-methylformate (IV); heating 9-oxo-1, 4-diphenyl fluoro-2-methyl formate (V) at 118 degrees C to obtain generating 9-oxo-1, 4-diphenyl fluoro-2-formic acid (VI), where (III) and (V) are obtained via processing Diels-Alder reaction of 1,3-diphenyl-indene (a) pentalene-2, 8-dione and methyl propiolate; and reacting with 4,4'-di-tert-butyl-2-bromobiphenyl lithium salt, and carrying out cyclization.    USE - Method for the preparation of dispirofluorene-indenofluorene derivative (I) or (II) (claimed) used in an organic electroluminescence and small organic molecule solar battery.    DETAILED DESCRIPTION - Preparation of dispirofluorene-indenofluorene derivative of formula (I) or (II) comprises:    (A) heating 9-oxo-1,4-diphenyl fluoro-3-methylformate of formula (III) to 118 degrees C, reacting, and generating 9-oxo-1,4-diphenyl fluoro-3-methylformate;    (B) heating 9-oxo-1, 4-diphenyl fluoro-2-methyl formate (V) at 118 degrees C, reacting, and generating 9-oxo-1, 4-diphenyl fluoro-2-formic acid (VI), where (III) and (V) are obtained via processing Diels-Alder reaction of 1,3-diphenyl-indene (a) pentalene-2, 8-dione and methyl propiolate;    (C) stirring at room temperature under the condition of concentrated sulfuric acid to obtain 6-phenyl-5, 8-dioxo-inden (2, 1-c) fluorene of formula (VII) and 5-phenyl-7, 12-dioxo-indene (1, 2-a) fluorene of formula (VIII); and    (D) reacting with 4,4'-di-tert-butyl-2-bromobiphenyl lithium salt at - 78 degrees C under the protection of nitrogen, and carrying out cyclization under the heating and backflow condition of glacial acetic acid and concentrated hydrochloric acid; where the mole ratio of (VII) and (VIII) to 4,4'-di-tert-butyl-2-bromobiphenyl lithium salt is 1:2-5.    INDEPENDENT CLAIMS are included for:    (1) an ethyl substituted indenofluorene derivative of formula (IX) or (X) formed by introducing an ethyl group on 6-phenyl indene (2, 1-c) fluorene and 5-phenyl indene (1, 2-a) fluorene;    (2) preparing an ethyl-substituted indenofluorene derivative comprising carrying out Huang Minlon reaction by reacting 6-phenyl indene (2, 1-c) fluorene and 5-phenyl indene (1, 2-a) fluorene with n-butyllithium and bromo-ethane under the protection of nitrogen at 78 degrees C, where the mole ratio of 6-phenyl indene (2, 1-c) fluorene and 5-phenyl indene (1, 2-a) fluorene, n-butyllithium, and bromo-ethane is 1:5:5;    (3) synthesizing trimerization indene of formula (XI) and (XII) comprising heating cyclization of 1,4-diphenyl-2, 3-di(hydroxymethyl) fluorene, and reacting at 180-220 degrees C;    (4) a mono-substituted trimerization indene derivative of formula (XIII) and (XIV) obtained via connecting ethyl and keto-carbonyl on the methylene of trimerization indanone; and    (5) preparing (XIII) and (XIV) by processing cyclization for 1, 4-diphenyl-2, 3-di (hydroxymethyl)-9, 9- diethyl fluorene, and controlling the temperature at 180-220 degrees C.