X-ray Computerized Tomography at micrometer resolution (muCT) is an important tool for understanding the properties of wood fibre materials such as paper, carton and wood fibre composites. While many image analysis methods have been developed for muCT images in wood science, the evaluation of these methods if often not thorough enough because of the lack of a dataset with ground truth. This paper describes the generation of synthetic muCT volumes of wood fibre materials. Fibres with a high degree of morphological variations are modeled and densely packed into a volume of the material. Using a simulation of the muCT image acquisition process, realistic synthetic images are obtained. This simulation uses noise characterized from a set of muCT images. The synthetic images have a known ground truth, and can therefore be used when evaluating image analysis methods.