The structural, electronic, and magnetic properties of double metallocene nanowires PnM(2) (Pn = C8H6, M = V, Cr, Mn, Co, and Ni) are investigated within the framework of gradient-corrected density functional theory. The PnMn(2) nanowire is predicted to be ferromagnetic white other nanowires are either antiferromagnitic or nonmagnetic. In addition, the PnMn(2) nanowire exhibits zigzag-like structural distortion that might result from the Peierts instability. The PnV, nanowire has the largest cohesive energy and shortest metal-metal distance and is likely the most stable structure among the 1D double metallocene nanowires.