Recently,sand fences,made of high density polyethylene(HDPE)board,which is resistant against harsh plateau environmental conditions,could possibly be used to control the wind-blown sand along the Qinghai section of the Golmud-Korla Railway.In this paper,wind tunnel simulation was performed on the protective effect of multiple rows of HDPE board sand fences on wind-blown sand.Two parameters have been used to reflect the protective effect of sand fences,that is,windproof efficiency and sand control efficiency,referring to the reduction rates of wind speed at a height of 0.04 m and sand flux in a run of test with the fence compared those in the control run of test without it,respectively.The test results showed that when the porosity was 30％,the single-row sand fence had the best wind proof and sand control efficiency with respective values of 46％and 65.3％.The windproof efficiencies of double-row and triple-row sand fences at 20H were 59％and 62％,respectively.Compared with the windproof effi-ciency of the single-row sand fence,those of the two-row and three-row fences increased by 13％and 16％,respectively:The maximum sand control efficiency of the double-row and triple-row sand fences were 92.1％and 96.5％,increased by 26.8％and 31.2％,respectively,compared with that of the single-row sand fence.This study indicates that the sand control efficiency after adding one or two rows was not double or triple that of the single-row fence,while the first-row sand fence played a major protective role.Compared with the double-row sand fences,the effect of the third row sand fence in triple-row sand fences is limited,and thus double-row HDPE board sand fences with the porosity of 30％are rec-ommended to control wind-blown sand along the Qinghai section of the Golmud-Korla Railway.