There　is　a　high　proportion　of　social　groups　in　crowds.　The　influence　of　social　groups　on　crowd　mobility　is　particularly　evident　in　emergency　situations　and　in　confined　movement　environments.　However,　studies　on　the　characteristics　of　social　group　movement　through　a　bottleneck　with　different　widths　are　limited.　Therefore,　the　computation　and　simulation　are　performed　in　a　corridor　with　a　bottleneck　involving　individuals　and　three　types　of　groups　(namely　two-person,　three-person　and　four-person　groups)　using　a　modified　multi-grid　model.　The　original　multigrid　model　is　modified　by　introducing　interactions　between　pedestrians,　avoidance　behavior　and　group　behavior,　and　validated　by　data　from　a　controlled　experiment.　It　is　found　that　the　group　configuration　can　be　adjusted　to　the　changing　scenarios　during　the　passing　movement.　The　movement　efficiency　and　level　of　walking　comfort　for　pedestrians　are　significantly　improved　in　wider　bottlenecks.　Passing　efficiency　is　evidently　increased　and　congestion　is　reduced,　when　social　groups　occupy　a　large　proportion　of　the　crowd　in　a　narrow　bottleneck.　These　numerical　findings　may　provide　new　insights　for　analyzing　nonlinear　pedestrian　social　group　dynamics.