In　the　gas-liquid　two-phase　flow,　gas　plug　may　rupture　after　its　formation　due　to　terrain　changes,　transmission　equipment,　and　other　human　factors,　which　may　cause　fluctuations　on　flow　state　and　pressure　of　the　fluid.　In　order　to　study　the　gas　plug　rupture　mechanism　of　slug　flow,　physical　and　mathematical　model　was　established,　focusing　on　the　effects　of　gas-liquid　two-phase　flow　parameters　and　pipeline　geometry　size,　the　influence　of　pressure　fluctuation　caused　by　the　gas　plug　rupture　was　analyzed.　The　results　show　that　when　other　factors　were　under　the　same　circumstance　and　the　length　of　gas　slug　were　same,　with　the　increase　of　the　liquid　ratio　held,　the　pressure　drop　amplitude　of　the　upstream　pipeline　was　increased,　and　with　the　increase　of　pipeline　diameter,　liquid　slug　size,　and　mixture　velocity,　the　pressure　drop　amplitude　of　the　upstream　pipeline　was　decreased.　©　2017,　Editorial　Office　of　＂CHEMICAL　ENGINEERING＂　(CHINA).　All　right　reserved.