Hydroxyapatite ceramics for biomedical applications are used in form of layers, granulates and bulk materials. A new method to produce layers or bulk materials is the electrophoretic deposition. To achieve layers with a thickness between 5 and 50 m the use of a fine powder with particle size in the sub micron range is essential. In this work we show that commercially available hydroxyapatite powders, which usually have a strong tendency to agglomerate, can be milled to particle sizes smaller than 500 nm. Using one of these powders and optimizing the parameters for the electrophoretic deposition thin, homogenous layers were produced.