Overlap joint of the FeSiB amorphous ribbon with thickness about 25 μm is successfully fabricated by micro pulsed laser. Effect of main process parameters including pulse power P, pulse width T, pulse frequency F on the weld forming is studied, and then the variation trend of mechanical properties is analyzed. The results indicate that the perfect weld forming and excellent mechanical properties can be obtained when P and T are matched appropriately, i.e. P is 4.8~7.2 W, T is 1.5~1.9 ms, and corresponding energy E is 0.9~1.2 J. With the increase of T, the microhardness of heat affected zone and weld zone decreases gradually. However, with the increase of P, the microhardness increases first and then decreases. With the increase of P and T, tensile strength of joint increases first and then decreases. The highest average microhardness of about 1300 Hv and 1000 Hv in the heat affected zone and weld zone is obtained, respectively, and the tensile strength exceeds 363 MPa, when P is 7.2 W, T is 1.7 ms, and F is 1.5 Hz.