Droplet　breakup　in　an　asymmetric　bifurcation　with　two　angled　branches　is　studied　experimentally　and　theoretically　in　this　paper.　In　order　to　tune　the　droplet　size　and　droplet　velocity　separately,　a　diluting　channel　is　added　and　its　influence　on　droplet　generation　is　confirmed　to　be　negligible.　The　underlying　physics　of　the　droplet　generation　is　revealed　as　compared　with　other　works.　Effects　of　the　droplet　parameters,　including　the　initial　droplet　length　and　the　droplet　velocity,　on　breakup　characteristics　are　analyzed.　The　regime　diagram　of　the　droplet　breakup　and　the　critical　conditions　between　different　regimes　are　provided.　It　is　found　that　the　splitting　ratio　is　largely　influenced　by　the　initial　droplet　length　and　the　droplet　velocity,　which　indicates　that　the　breakup　process　is　an　inter-dependent　process　between　the　splitting　junction　and　droplets　themselves.　At　last,　a　simple　but　effective　prediction　model　is　constructed　by　considering　the　hydrodynamic　resistance　of　the　branches　with　the　presence　of　the　daughter　droplets,　which　also　proves　the　similar　motion　of　the　droplets　with　low　viscosity　ratio　of　the　two　liquids　and　the　bubble.　(C)　2018　Elsevier　Ltd.　All　rights　reserved.