The 3-dimensional (3D) numerical modelling of flow in an open channel flow field of a group of submerged vegetation using a computational fluid dynamics (CFD) platform was performed in this study. Using the Acoustic Doppler Velocimetry (ADV) experimental data as benchmark solution, a comparative analysis is obtained with the numerical results of CFD. A quantitative comparison was performed on several hydrodynamic variables that impact submerged vegetation in an open channel flow, such as flow depths, streamwise water velocity, turbulent intensity, and the Reynold’s shear stress. In the numerical analysis, flow turbulence was found using RANS approach of RNG k-ε while a Volume of Fluid (VOF) method is used to track the air–water interface. Structured meshes of cubic elements are used to discretise the channel geometry. In this study, the presented numerical model has accurately reproduced the measured flow field, besides showed good agreement with the experimental data for the analysed turbulence variables, i.e. with less than 10% discrepancy. This study concludes that the CFD platform can be utilised as an acceptable and efficient analysis tool for simulations of the flow field surrounding a group of submerged vegetations. For further analyses, more simulated points along the channel (i.e. in the sensitive areas with heavy turbulence characteristics alteration) can be compared with experimental data. Further validation analysis will also involve comparing the numerical and experimental data with canopy effect created within vegetation patch (i.e. to investigate flow turbulence effect generated by spacings within the patch).