Abstract: Disclosed are a liquid crystal composition comprising a liquid of formula I and formula II-B, and a liquid crystal compound and a related liquid crystal display device wherein R0, R1, R2 and R3 each independently represent an alkyl group having a carbon atom number of 1-10, a fluoro-substituted alkyl group having a carbon atom number of 1-10, an alkoxy group having a carbon atom number of 1-10, a fluoro-substituted alkoxy group having a carbon atom number of 1-10, an alkenyl group having a carbon atom number of 2-10, a fluoro-substituted alkenyl group having a carbon atom number of 2-10, an alkenoxy group having a carbon atom number of 3-8 or a fluoro-substituted alkenoxy group having a carbon atom number of 3-8, and any one or more non-connected CH2 in R0, R1, R2 and R3 may be substituted with cyclopentyl, cyclobutyl, cyclopropyl or —O—; Y represents ethyl or ethenyl; each independently represent one of and any fluorobenzene; represents benzene or fluorobenzene; and m represents one of 1, 2 a