  In present work an experiment has been designed to measure the Rayleigh ratio
directly at $405$ nm and $432$ nm for linear alkylbenzene which is a common
solvent used in liquid scintillator detectors of neutrino experiments. The
perpendicularly polarized Rayleigh ratio is determined to be $(4.52\pm
0.28)\times 10^{-6}$ m$^{-1}\cdot$ sr$^{-1}$ at $405$ nm and $(3.82\pm
0.24)\times 10^{-6}$ m$^{-1}\cdot$ sr$^{-1}$ at $432$ nm, and the corresponding
Rayleigh scattering length is $L_{Ray} = 22.9\pm 0.3(\mathrm{stat.})\pm
1.7(\mathrm{sys.})$ m at $405$ nm and $L_{Ray}= 27.0\pm 0.9(\mathrm{stat.})\pm
1.8(\mathrm{sys.})$ m at $432$ nm.
