Abstract: Through numerical simulation, the appropriate secondary reinforcement modes and reinforcement ranges have been studied in this paper based on the soil layer structure of a typical deep foundation pit in Kunming, Yunnan province. As shown by calculation, when the one section reinforcement scheme is adopted at the central of foundation, the horizontal dis placement of foundation pit wall scarcely increased after the secondary reinforcement range larger than 0.54l(l:the length of foundation pit sidewall), when the two section reinforcement scheme is adopted at the central of foundation, the horizontal dis placement of foundation pit wall scarcely increased after the secondary reinforcement range larger than 0.18l. The two section reinforcement scheme is superior to the one section reinforcement scheme on the cost and reinforcement effect. The results of this paper providing a reference to similar projects.