Base　saturation　flow　rate　(BSFR)　is　one　of　the　key　factors　of　signal　intersection　analysis.　Highway　Capacity　Manual　2010　suggests　a　default　value　of　base　saturation　flow　rate　is　1900　pcu/h/ln　without　local　value.　However,　the　BSFR　varies　depending　on　driver　behavior　and　traffic　environment.　Its　accurate　determination　is　of　prime　importance　in　signalized　intersection　planning　and　designing.　Hence,　researching　BSFR　in　Beijing　is　necessary.　In　this　paper,　the　influence　of　regional　type　on　the　basic　saturation　flow　rate　is　studied　based　on　the　Canadian　Capacity　Guide　for　Signalized　Intersections　(CCG).　To　simplify　the　research　process,　through　lane　base　saturation　flow　rate　(TLBSFR)　was　studied　using　32　through　lanes　at　16　signalized　intersections.　Using　a　5%　level　of　significance,　there　were　no　significant　differences　between　the　suburban　BSFR　and　downtown　BSFR　with　ANOVA.　After　comprehensive　consideration,　a　TLBSFR　value　of　1550　puc/h/ln　was　determined　and　recommended.　©　2018　American　Society　of　Civil　Engineers.