Abstract: Based on unsaturated soil recognition of loess disasters, this paper designs a vertical permeameter instrument on unsatu-rated soil. Experiment instrument consists of precipitation, runoff, seepage(sampling) and enrichment devices. It has important significance for studying on loess disasters and to simulate permeation process in loess under atmospheric precipitation and irrigation water. It can obtain parameters of seepage path, infiltration front velocity and water volume. The paper has established correlation between runoff volume and time(runoff velocity),displacement of infiltration front and time(seepage velocity),seepage volume and times(enrichment velocity).Experiments are conducted using unsaturated intact loess. The test results show that the experiment instrument is simple and useful, and can obtain permeation parameters of loess better.