Replacing or minimizing the use of halogenated organic solvents in the processing and manufacturing of conjugated polymer based organic electronics has emerged as an important issue due to concerns regarding toxicity, environmental impact, and high cost. In this work, we report the development of water and alcohol processable nanowires (NWs) with well-defined crystalline nanostructure based on the solution assembly of azide functionalized poly(3-hexylthiophene), and subsequent photo-crosslinking and functionalization of these NWs. The solution assembled P3HT-azide NWs were successfully crosslinked by exposure to UV light, resulting in highly stable NWs. Residual azide units on the photo-crosslinked NWs were then functionalized with alkyne terminated polyethylene glycol using click chemistry. PEG functionalization of the crosslinked P3HT-azide NWs allowed for stable dispersion in alcohols and water, while maintaining well-ordered NW structures with electronic properties suitable for the fabrication of organic field effect transistors.