Ensuring the seepage safety o f earth dams is always the concern o f managers, owners, and consumer, those are in need o f water from the reservoir. The establishment o f the relationship between the seepage analysis, the standard dataset and the monitoring data is a sufficient Step to complete safety assessment for hydraulic works in general and earth dams in particular. This article focuses on assessment the seepage safety for earth dam from three states o f a standard dataset. The detailed quantification o f three levels o f seepage safety assessment is based on the state o f the earth dam's material, seepage conditions, and reservoir water level... Moreover, these results are used to evaluate the phreatic surface position -thereby, assessing seepage safety issues. This is a big step forward in calculation and management o f hydraulic works. The calculation results are presented scientifically, easy to look up in the assessment o f seepage safety in earth dam.