Bus　passengers＇　boarding　and　alighting　behavior　is　important　content　when　researching　bus　operation　efficiency.　This　paper　uses　an　improved　cellular　automata　(CA)　model　and　introduces　four　dynamic　parameters　to　study　individual　behavioral　characteristics　of　bus　passengers＇　boarding　and　alighting　behavior.　The　research　on　the　relationship　between　the　macro　pedestrian　flow　formed　by　the　interaction　between　the　individual　passengers　and　the　stop　time　of　the　bus　station　was　realized.　Then　it　was　modeled　for　different　situations,　and　the　general　update　rules　of　CA　were　set　based　on　realistic　situations.　The　passenger　boarding　and　alighting　behaviors　of　the　No.　245　bus　route　in　Nanchang,　China　were　simulated,　and　the　simulation　results　of　four　different　door　layouts　and　passenger　boarding　and　alighting　modes　were　compared.　It　was　found　that　when　the　passenger　loading　rate　in　the　bus　reaches　65%,　the　passenger　boarding　rate　has　an　obvious　tendency　to　slow　down;　the　width　of　the　door　has　a　direct　relationship　with　the　passenger　alighting　efficiency,　and　the　bus　stopping　time　can　be　reduced　by　adjusting　the　width　of　the　alighting　door;　a　strategy　which　allows　passengers　board　on　the　bus　via　the　alighting　door　may　effectively　reduce　the　bus　stopping　time　when　there　are　many　passengers　boarding　on　the　bus.　Using　strategy　four,　simulation　research　found　that　Bus　No.　245　can　reduce　the　stopping　time　by　40-50%　in　some　station　scenarios.　Research　results　show　that　the　CA　model　has　certain　practical　value　and　can　provide　a　theoretical　reference　for　public　transportation　control　and　management.