We developed a simple but efficient method to mass-produce highly flexible and high-performance photodetectors based on aligned cadmium sulfide (CdS) nanowire (NW) networks. In this method, the CdS NWs were selectively aligned along the molecular patterns on flexible substrates via a direct assembly method, and the aligned CdS NW patterns were utilized as the channels of flexible photodetectors. The photodetectors based on the aligned CdS NWs exhibited ∼10 times higher photosensitivity and ∼100 times faster photoresponse than those based on randomly oriented NW networks. In addition, the flexible photodetectors exhibited stable photoconductive characteristics even when these were bent down to the radius of curvature of 0.2 mm. This research may pave the way for the large-scale fabrication of low-cost and high performance flexible photodetectors based on the aligned NW networks.