Open AccessThis paper presents reliable synthesis of germanium nanowires by the vapor-liquid-solid method using copper as an alternative catalyst to gold, the most commonly used metal. The morphological study showed long range single-crystalline germanium nanowires with diamond structure and diameters ranging from 20 nm to 80 nm and lengths in tenths of a micrometer, which was much larger than the cross-section. In an investigation of electronic properties, devices built from a thin film of nanowires were studied and the semiconductor behavior of the samples confirmed, with variable range hopping identified as the main transport mechanism. Additionally, metal-nanowire contact behavior - ohmic or with Schottky barrier - was found to depend on the metal used in the device. Therefore, the possibility of controlling current-voltage behavior combined with the good crystalline quality of the nanowires renders these nanostructures an attractive option for future electronic and optoelectronic applications.