The invention discloses an automatic riverway water level recording and warning water level exceeding alarm device, and relates to a riverway water level recording device. A square block floating ball (8) sleeves a water level ruler (11); a camera (6) is arranged inside a hole in the front part of the square block floating ball; the camera is connected with a battery which is also a processor in a 4-G signal transmitting box (14) at the upper end of the water level ruler through a radio data line (12); a triggering switch (9) is arranged at the lower part of a side plate (10) on one side of the upper part of the water level ruler; the triggering switch is connected with the battery which is also the processor in a 4-G signal transmitting box through a data line (13); the processor is used for transmitting data to a signal processor DSP of a duty room computer (3); or the alarm data is transmitted to a voice box (1) of the computer to make alarm voice. By adopting the camera, the water level change data can be collected and stored in the computer, when danger happens, the signal is transmitted to the computer through the triggering switch, and a voice box alarm is made, so that the danger can be found conveniently in time.