As a consequence of substantial advances in computer-aided design and manufacturing technology, engineering parts are no longer restricted to combination of simple geometrical shapes. Implementing complex curved surfaces in engineering components in combination with finite-element geometry optimization has become a prevalent means of designing a part. Measuring residual stresses using X-ray diffraction (XRD) on complex curved surfaces requires further development of current measurement methods. Here we investigate how a laboratory XRD system equipped with a five-axis stage and two-dimensional detector can execute sin2ψ residual stress measurements on curved surfaces. Shadowing that blocks the diffracted beam to reach the detector was avoided using proper rotations and tilting of the sample. A standard video-laser alignment system commonly used to manually place the sample in the center of diffraction was used to also generate virtual maps of the sample's curved surfaces on a fine mesh grid. The geometry was then used for setting the required rotations and tilt angles. A set of diffraction frames collected using this method on a model zirconia dental ceramic, afforded the opportunity to superimpose phase and stresses on a complex geometry. This is a step forward for the XRD technology, and its usefulness applies to many different industries.