Anti-reflux drainage bag with serial partition and drainage and sampling method

The invention provides an anti-reflux drainage bag with a serial partition and a drainage and sampling method, and relates to the technical field of medical instruments, and the anti-reflux drainage bag comprises a drainage tube and a drainage bag; the drainage tube penetrates through the drainage bag, and a check valve is arranged in the section, located in the drainage bag, of the drainage tube. The drainage bag comprises a plurality of partitions, the flow stop valve can be communicated with the drainage tube or the partitions or can be communicated with the drainage tube and the partitions at the same time, and the drainage tube can be communicated with the specific partitions but not communicated with other partitions by adjusting the flow stop valve. The problem that the compartments are mutually polluted when an existing drainage bag with serially connected compartments is used for collecting drainage liquid is solved; drainage liquid in a specific partition can enter the drainage tube to be discharged