The current study conducted a finite element (FE) and experimental investigation on tubular channel angular pressing as a noble severe plastic deformation technique for producing ultrafine grained and nanostructure tubular components. To examine the effects of the TCAP process on the strain distribution and deformation behavior, FE simulations were employed. The FE results demonstrated that equivalent plastic strain of 2.1-2.9 was developed after applying one pass TCAP. Analytical investigations were carried out to calculate the accumulated strain during the process. Tube thinning in the early stages of the process was observed as a result of tensile circumferential strains but this could be compensated for by the back pressure effect resulting from the next shear zones and also compressive circumferential strain resulting from decreasing the tube diameter. Microstructural observations showed significant grain refinement after one pass TCAP on AZ91 magnesium alloy at 300 ºC. Microhardness measurements demonstrated increasing hardness to 78 HV from the initial value of 51 HV.