A liquid chromatography device includes a sample inlet valve to which a sample to be analyzed is introduced, and a trap valve fluid-communicating with a solid phase extraction column and a reverse phase liquid chromatography column. The device further includes a solvent dividing unit dividing flow of a solvent discharged from the sample inlet valve into the first solvent inlet port and the second solvent inlet port of the trap valve. The liquid chromatography device improves resolution and increases reproducibility by allowing the sample injecting direction and the sample eluting direction to be opposite to each other.