A scheme of measuring liquid refractive index based on linear CCD is proposed．The parallel beam emitted by laser converge through a lens，and a linear CCD is set at the convergence point to measure the diameter of the beam．After liquid is inject into the container behind the lens，the beam is refracted，and the refractive index can be measured by the variation of the beam diameter．The refractive index of distilled water and ethanol obtained by experiment is consistent with the standard value，and the relative error is less than 0．4%．Especially，the refractive index can be measured only by measuringthe variation of the beam diameter for different liquids．The scheme has the advantages of simple structure，simplified operation and accurate easurement，which has application value in physics experiment teaching and research on manufacturing refractive index measuring instrument．