The recently deposited stratum is a typical shallow and relatively weak layer of the main soil layer involved in project construction in Beijing area. The variation of soil mechanics index is great. Based on a large number of practical engineering in Beijing area, shear strength variability and spatial variability of soil property parameters are associated by means of stochastic field model of soil profile. Variation laws of the correlative distance and spatial variability coefficient are gained by statistic analysis of shear strength indexes of recently deposited typical stratum. The autocorrelation distance of newly deposited soil layers of Beijing area is generally 3~4 m, which is a suitable sampling interval.