摘要： 现用于土石坝水平位移观测的仪器主要为引张线式水平位移计、电测式水平位移计，本文对这两类仪器性能进行了比较。

Abstract: At present，there are two kinds of horizontal displacement gauges for earth-rock dams, that is, mechanical tension wire displacement gauge and electrical horizontal displacement gauge. In this paper the comparison of their properties is presented.