Abstract: Based on the interval features of mechanic parameters of retaining walls and the interval probability of reliability analysis mode,the interval analysis method was introduced to establish non-probabilistic reliability analysis mode for the structural system of retaining walls in which uncertain geotechnical mechanic parameters was regarded as interval variables.In terms of the limitation and shortage of the interval calculating rules,the interval-truncation approach were adopted to determine the range of functional function in order to avoid the interval expansion of functional function while optimization methods were adopted to calculate the non-probabilistic reliability index of retaining walls.It was shown by the simulated results of practical projects that the proposed method was reasonable and reliable.