Disclosed are a structure of a flow measurement sensor based on time-of-flight and a method for installation thereof, the structure comprises at least one pair of a first flow measurement sensor and a second flow measurement sensor vertically installed on a pipeline wall, a beam transmit-receive end both provided respectively at a bottom of the first flow measurement sensor and the second flow measurement sensor and is capable of emitting and receiving beams, a beam straight line formed between a first beam transmit-receive end and a second beam transmit-receive end does not intersect with an axis of the pipeline, and forms, with the axis of the pipeline, an included angle less than 90° .