Abstract: In the presence of sea-surface multi-path mono-pulse radar measure a low elevation target is difficulty, and its precision cant satisfy the requirement of ballistic trajectory measurement in shooting range. We apply the dynamic bias compensation algorithm calculate the elevation of low-altitude after measurement from the saved video signal by the radar system used in navy range. Result indicates dynamic bias compensation is effective and feasible in the off-line elevation extraction and it can remarkably improve the precision of elevation measurement. Then offer the gist for experimentation decision-making.