A liquid crystal medium is described, which has stability to heat, light and so on, a wide temperature range of liquid crystal phase, a large optical anisotropy and a large dielectric anisotropy, and exhibits an optically isotropic liquid crystal phase. The liquid crystal medium includes a liquid crystal compound represented by formula (1) and a chiral reagent and exhibits an optically isotropic liquid crystal phase. For example, R1 is C1-C20 alkyl; the rings A1-A6 are each 1,4-cyclohexylene, 1,3-dioxan-2,5-diyl, 1,4-phenylene, or 1,4-phenylene with arbitrary hydrogen atom being replaced by a halogen atom; Z1-Z6 are each a single bond; L1-L4 are each a hydrogen atom or a halogen atom; X1 is a hydrogen atom or a halogen atom; each of l, m, n, o, p and q is 0 or 1, and the sum of them is 3.