The authors report the growth of high density ternary Zn1-xCdxSe (x=0.1,0.3) nanowires on an oxidized Si(100) substrate by molecular beam epitaxy and the fabrication of ZnCdSe nanowire photodetectors. It was found that the as-grown ZnCdSe nanowires exhibited mixture of cubic zinc-blende and hexagonal wurtzite structures. It was also found that the average diameters for the Zn0.9Cd0.1Se and Zn0.7Cd0.3Se nanowires were 36.0 and 70.6 nm, respectively, while the average lengths of Zn0.9Cd0.1Se and Zn0.7Cd0.3Se nanowires were both around 1 mu m. Furthermore, it was found that the turn-on and turn-off time constants of the fabricated photodetectors were both less than 3 s. (C) 2010 American Vacuum Society. [DOI: 10.1116/1.3431087]