We try to fabricate an ultra-thin beryllium bronze curved tapes for space elastic self-expanding boom (lenticular boom). The welding process is one of the difficult problems in development of lenticular boom. In this paper, the welding forming of ultra-thin beryllium bronze curved tapes is studied and technique parameters are optimized. Test results show that optimized technique parameters are welding voltage 180 V, pressure holding time 7 s. Also, after 340℃, 2 h heat treatment, nominal shear strength of welding joint increases from 52 MPa to 68 MPa. Finally, fracture mechanism of welding joint is related to welding energy closely, with increasing welding voltage, nominal shear fracture transfers from welding joints zone to heat affect zone.