The invention, which belongs to the evaluation field of geological disasters of water conservancy projects, especially relates to a measurement arrangement system for exploring a riverway karst cave and implementation method thereof, particularly to a multi-dimensional detection method for diagnosing a karst body hidden in a riverway by using a parallel electrical method. The multi-dimensional arrangement apparatus for exploring riverway karst body distribution comprises a test system and a test instrument. The test system consists of two multi-core cable lines arranged at two river embankments in parallel, infinity B electrodes corresponding to the single multi-core cable line, and potential reference N electrodes. 64 electrodes are arranged at each multi-core cable line; and each electrode channel is connected with the ground by a copper rod. The test instrument is a parallel electric method instrument. According to the multi-dimensional detection apparatus and method of exploring a riverway karst cave, because of utilization of the parallel electric method detection technology, the work efficiency of the conventional resistivity method is improved; with an interpreting technique based on combination of a two-dimensional apparent resistivity image and three-dimensional inversion imaging, the karst cave exploration precision is improved and defects in the prior art are overcome.