Abstract: In restricted waterways, double-propeller jet flows display stronger turbulence characteristics and more intricate vortex structures than single-propeller jets in open waters. This enhanced turbulence is linked to local bed erosion, channel adjustment, and ship vibration, exerting notable effects on channel stability and navigational safety. To further probe the underlying mechanisms, this study employs high-resolution flow-field data from indoor PIV tank experiments to examine differences in turbulence characteristics between single- and dual-propeller jets, and to evaluate the effects of section coefficient, propeller pitch, and rotational speed on turbulence intensity and Reynolds stress in the dual-propeller interaction zone. The results indicate that, relative to single-propeller jets, dual-propeller jets exhibit greater similarity between the jet features at the propeller axis and those outside the axis. In the central interaction region near the hull, the dual-propeller jet presents a more pronounced downward-inclined trajectory, producing stronger disturbance and erosion effects on the bed surface. The turbulence intensity of the dual-propeller jet in the interaction zone exhibits an “eccentric single-peak” pattern, with the peak appearing at the propeller-shaft height and diminishing downstream. A reduced section coefficient shifts this peak region closer to the bed. Turbulence intensity rises with decreasing pitch and increasing rotational speed. The vertical Reynolds-stress profile shows a “wide-top, narrow-bottom” pattern, with an upper “S-shaped” peak whose curvature strengthens as the section coefficient increases. The absolute Reynolds-stress magnitude grows as the pitch decreases. Under varying rotational speeds, the Reynolds stress maintains an “S-shaped” distribution, with smaller values above and larger values below, and the lower peak becomes more distinct. These findings enhance understanding of turbulence characteristics in twin-propeller jets within restricted waterways, offering a scientific basis for evaluating navigation-induced scouring and providing useful guidance for improving the long-term stability and safety of inland and coastal channels.