Under the influence of long term rainfall and human activity, a high and steep loess slope on the mountain behind a residential area in Wuqi County has become hidden danger of geological disaster. The combination treatment plan of load decreasing soil nailing to strengthen the stability of slope was put forward. Combined with the actual situation, the parameters, process requirements and construction methods of level-by-level slope cutting and soil nailing support were designed respectively. In accordance with the construction plan, the slope has been effectively strengthened.