The study explores the major challenges facing mixed migratory flows, it analyses the route source of migrants and the causes for flee, which is facilitated by different factors. The study is based on data collected through review of available literature including journal, articles, reports, papers, textbooks and thesis. The researcher visited Different institutional libraries and intensively used online resources in undertaking this study. Findings shows that, challenges facing the country (Tanzania) includes; lack of policy on mixed migratory flow, uncoordinated legislations dealing with groups forming mixed migratory flows, the geographical nature of the country makes it hard for immigration officer to manage irregular migrants (border management), lack of finance and technical resources and lack of political will from the source countries where irregular migrants originates. The study realized that migration management is not simple task considering that each country has its own legal regime. Therefore, it is recommended that mixed migratory flow can longer be managed by national law of each state due to complexities accompanied by this type of migratory movement. The solution is to have a universal coordinated legal mechanism.