Optimum conditions with respect to preparation-determined fibre distribution in borosilicate glass composites were investigated. Continuous C-fibre bundles were impregnated with glass powder in silicon alkoxide solution and wound in parallel to prepregs which were hot pressed into unidirectional composites. The influence of the glass particle size during the impregnation of fibre bundles and during hot pressing on the homogeneity of the fibre distribution was of special interest, as well as the influence of pressure and temperature on the densification of the composites. Optimum conditions were related to optimum values in the bending strength of the resulting composites. Under the optimum hot-pressing conditions the fibre volume content was varied. It has been shown that the fibre distribution was much more homogeneous when fine-grained glass powder was used for impregnation. At high fibre volume concentrations of the composites the distribution was better than at low concentrations. High fibre concentrations were connected with fracture toughness of the sample, as shown by the three-point bending experiments, whereas samples with low C-fibre concentration showed brittle behaviour.