Organolead halide perovskites are becoming intriguing materials applied in optoelectronics. In the present work, organolead iodide perovskite (OIP) nanowires (NWs) have been fabricated by a one step self-assembly method. The controllable NW distributions were implemented by a series of facile techniques: monolayer and small diameter NWs were prepared by precursor concentration tuning; NW patterning was achieved via selected area treatment assisted by a mask; NW alignment was implemented by modified evaporation-induced self-assembly (EISA). The synthesized multifunctional NWs were further applied in photodetectors (PDs) and solar cells as application demos. The PD performances have reached 1.32 AW−1 for responsivity, 2.5 × 1012 Jones for detectivity and 0.3 ms for response speed, superior to OIP films and other typical inorganic NW based PD performances. An energy conversion efficiency of ∼2.5% has been obtained for NW film based solar cells. The facile fabrication process, controllable distribution and optoelectronic applications make the OIP NWs promising building blocks for future optoelectronics, especially for low dimensional devices.