The invention provides a novel river-flow type water turbine and belongs to the technical field of river-flow renewable energy. The novel river-flow type water turbine comprises a water wheel mechanism, a spindle mechanism and a supporting mechanism. The water wheel mechanism is formed by combining 2-10 water wheel units. Each water wheel unit comprises a center drum and blade mechanisms. The spindle mechanism comprises spindles, bearing brackets, first shaft plates and second shaft plates. The supporting mechanism comprises supports and bases. Sliding return pulleys below face plates of the supporting mechanism are located on slideways of the bases. The supports and the bases are fixed together through fixing mechanisms. Support slideways are sleeved with bearing bracket sliding grooves in the two sides of the bearing brackets respectively and fixed through bearing bracket bolts. The second shaft plates of the spindle mechanism are connected with connecting flanges at the two ends of the water wheel mechanism through bolts. The water turbine is simple in structure, low in weight, safe and reliable in operation and capable of being adaptive to different widths and depths of rivers as a power generation device, improving the working performance and utilization efficiency of water resources.