The detection is a real challenge for most of the UV-space missions. First, the classical detectors quantum efficiency is very low between 100 and 300 nm. The second point is that the useful flux is very low, and the photon counting is sometimes required. The stray light flux (visible light) is often strong so that additional filters are needed. In addition to the fact that these filters reduce the effective quantum efficiency, it is well known that the filter quality is a big constraint for the UV applications. For these reasons, dedicated detectors with high performances are required. Fortunately, strong improvement in detectors has been done for years and promising detectors are merging. After having reminded the different UV-space mission needs, this paper will present the available UV detectors. In the last part, the CNES Roadmap will be shortly discussed.