NOVELTY - A fluorene derivative (I) or (II), is new.    USE - New fluorene derivative is used for forming organic layer e.g. light-emitting layer, hole-injection layer, hole-transport layer, electron-transport layer and electron-injection layer for electronic device e.g. organic electroluminescent device, organic solar cell, organic photoreceptor and organic thin-film transistor (all claimed).    ADVANTAGE - The organic electroluminescent device containing the layer formed using the fluorene derivative has high luminance and durability, and reduced driving voltage.    DETAILED DESCRIPTION - A fluorene derivative of formula (I) or (II), is new.    R1-R4=H, deuterium, or 2-50C heteroaryl optionally containing sulfur, nitrogen, oxygen, phosphorus or silicon as hetero atom, 1-50C alkyl or 6-60C aryl (all optionally substituted), where at least two R1-R4 combines to form (un)saturated ring;    L=single bond, halo, cyano, 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 6-20C aryl alkyl, 7-20C aryl, 8-20C aryl alkenyl, 2-2C heterocyclyl optionally substituted by 6-60C aryl or halo, or acetylene containing O, N or S as hetero atom;    Ar1,Ar2=D, 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 6-20C aryl, 8-20C aryl alkyl, 7-20C aryl alkenyl, 2-20C heterocyclyl substituted with substituents chosen from cyano or optionally substituted acetylene, 1-50C haloalkyl, amino, amino, nitro, 1-20C alkyl amine, 1-20C alkyl thiophene, 6-20C aryl thiophene, 2-20C alkynyl, 3-20C cycloalkyl 8-20C alkenyl aryl, or groups derived from silane-based compound, boron-based compound or germanium-based compound;    o=0-2;and    n,m=1-4.    An INDEPENDENT CLAIM is included for organic electroluminescent device, which has an organic layer formed between anode (102) and cathode (108).    DESCRIPTION OF DRAWING(S) - The drawing shows the schematic structure of organic electroluminescent device. (Drawing includes non-English language text)    Substrate (101)    Anode (102)    Hole-injection layer (103)    Hole-transport layer (104)    Cathode (108)