Additive manufacturing or 3D printing of components is now becoming a very attractive method of producing models and parts in the medical, automotive, aerospace, and clothing industries, among many others. Despite the numerous advantages associated with 3D printing of components, the uptake of this technology is still in the early stages, owing to the limited research and data availability on the process, safety of components, and their integrity. Material extrusion 3D printing process is currently being investigated for manufacturing of metal composites and is one of the interesting subjects in fused deposition modelling. This study investigates the effect of infill pattern (lines, gyroid, cross, and lines) and layer height (0.15 mm, 0.1 mm, and 0.2 mm) on the dimensional deviation and mechanical properties of 3D printed 17-4 PH/PLA composites. The samples were produced through fused deposition modelling and evaluated for dimensional stability and tensile properties. In terms of dimensional accuracy, it is observed that for all samples, the width had the highest accuracy, followed by the height and finally the length. The largest width errors were observed for samples prepared at a layer height of 0.15 mm and gyroid infill patterns. The smallest width errors were observed on samples fabricated at a layer height of 0.2 mm and lines infill pattern. As expected, 3D printing at the lowest layer height of 0.1 mm resulted in the minimum dimensional error of the length of these samples. The lowest mechanical strength was reported at samples fabricated at an infill pattern of lines and layer heights of 0.1 mm and 0.2 mm.