A response of around surrounding to an adjacent deep foundation pit safety risk fuzzy synthetic evaluation model was established by according to the basic principle of fuzzy math.Based on the monitoring data of the deep foundation pit,the monitoring data was evaluated quantitatively by using the method of fuzzy synthetic evaluation,and then safety grades of foundation can be determined.The result proves that the method can reflect the risk condition of deep foundation pit and reduce the errors caused by subjective judgment.The assessment makes the evaluation results accurate and could guarantee the development of the project.