The optic characters of high power laser diode linear arrays are analyzed, and a device is designed to reshape its laser beam, the emission of a 10 mm width continued wave laser diode linear arrays can be coupled into a fiber by the device. The laser beam of laser diode is collimated in fast direction by a cylindrical micro lens, then a pair of step-mirrors symmetries the beam parameter products in fast direction and slow direction, and a focusing lens couples the light into an optical fiber. Experiment is carried out, the emission of a laser diode linear array with 42 W laser power was coupled into a fiber witii the core diameter of lmm and numerical aperture of 0.38. The output power of 25 W from the fiber is obtained with the coupling efficiency of 59.5%.