Abrasive waterjet turning (AWJT) is an advanced machining process that could be used for turning cylindrical workpieces with the advantages of low vertical forces and negligible thermal distortion. Radial-mode AWJT is characterised by better utilisation of jet energy and high material removal rate. However, the prediction of depth of cut (DOC) is difficult due to the interaction of several process parameters. In this paper, a new finite element (FE) model was developed to predict the DOC in radial-mode AWJT. The workpiece material is AISI 4340 alloy steel and it is modelled with Johnson-Cook (JC) constitutive model. Two AWJT parameters: waterjet pressure and abrasive flow rate, were considered in the FE model with three levels for each parameter. A full factorial design was selected to evaluate the combined effect of these independent parameters. The resulting crater profile was utilised to estimate the DOC at each parameter combination. In order to evaluate the model accuracy, the DOC results were compared with published experimental data from the literature at the same AWJT conditions. The comparison showed a good agreement between the FE results and the published experimental results.