In order to study the interaction effect of multiple foundation pit support forms in complex surrounding environment, with a deep foundation pit project with complex surrounding building environment taken as an example, based on the analysis of pit support experience and theoretical calculations, a variety of support methods has thus been adopted including row piles + slant support, internal bracing, reserved back pressure soil, etc. A monitoring has been made of the top displacement, deep horizontal displacement, internal support force, and vertical displacement around the support piles, with a finite element analysis conducted by using MIDAS GTS NX, followed by a comparison and analysis of the actual monitoring data with the finite element analysis data. The results show a good agreement, indicating that the combination of multiple support schemes is reasonable and reliable, thus achieving the support effect.