Left ventricular assist device (LVAD) is a successful and useful treatment method for end-stage heart failure. An important part-hydrodynamically suspended impeller exposed to corrosive conditions, is required to be sealed hermetically into micro packages. Laser beam welded Ti6Al4V alloy is adopted in anti-corrosion micro packages for the LVAD impeller. Thin and narrow welds are required for such medical equipments. Pulsed Nd∶YAG welding is successfully adopted as sealing method for the impeller. The experimental results show that peak power of 414 W, welding speed of 360 mm·min-1, and overlap of 70% are the final selection of the main laser welding process parameters. Welded joints along the direction of welding line are uniform and stable, the welding line is good, and the heat-affected zone is narrow. There is little difference between welded joints and base metal in terms of mechanical properties. Porosity, inclusions, cracks and other defects are not found.