The invention relates to the technical field of flow monitoring, in particular to a rotor flow meter with easily assembled connecting bend tubes. The rotor flow meter comprises a rotor flow meter body, the rotor flow meter body comprises a glass graduated tube, a measuring floater and a mandrel, wherein the measuring floater is positioned inside the glass graduated tube, and the mandrel is fixed into the glass graduated tube and used for guiding a lateral floater. According to the rotor flow meter with the easily assembled connecting bend tubes, a top connecting bend tube and a bottom connecting bend tube are fixedly clamped to the outside ends of a top mounting base and a bottom mounting base through assembly clamp plates, the top connecting bend tube and a top linkage tube at the lower end of the bottom mounting base are inserted into internal through holes to control the communication state between the connecting bend tube and the mounting base, so that the rotor flow meter is applicable to flow measurement of a horizontal pipeline, wider in applicable range and convenient to assemble and disassemble and can automatically cut off after disassembly.