Numerical simulation was carried out for the twin-jet flow generated by a plane wall jet and a parallel offset jet at an offset ration of s/h = 1.0 (4.5 < Fr < 8.0) by using Volume of Fluid (VOF) RNG k – ε turbulence model. As the jet fluid exited the two orifices, the shear layer between the jet and ambient fluid drove the ambient fluid entrainment into the jets. The simulation results were then compared with experimental results published in literature. The results of simulations were conducted to quantify the influence of the Froude number on the distances from the source to the merging point and combined point. The results show that the flow pattern in the stilling basin show a mixing flow pattern of impinging jet and submerged hydraulic jump. In the converging region, the velocity distribution shows a combination of wall jet and submerged hydraulic jump; while in the combined region, the velocity distribution is expected to behave like a single wall jet. The energy dissipation ration is larger than that of classical jump and it reaches above 70% at Fr > 7.0.