To improve the mechanical strength of the honeycomb panel heat exchanger and ameliorate the limit of swellcrush forming, the main factors which affecting the welding limit cohesion and limit strength of stamping rupture were optimized. These factors included the welding shape, welding power, welding speed, welding distance, and welding arrangement. The single factor experiment and multi factors experiment for welding sheet mechanical strength were carried out with digital controlled laser welder, pulling test rig, hydraulic pressure pump and other apparatuses. The results of the single factor experiment showed that the sheet limit mechanical strength of spiral welding spot was the largest. With the increase of welding power and welding speed, the limit mechanical strength of spiral welding spot first increased then decreased. The limit strength of stamping rupture of equilateral triangle arranged welding spot was relatively good. With the increase of welding distance, the strength decreased rapidly. The result of orthogonal experiment showed that: with the spiral welding spot and equilateral triangle arranged welding spot, the maximum limit strength of stamping rupture reached 8.6MPa which was improved by 7.5% compared with current welding technology when the welding distance was 50mm, welding power was 2.2kW, and welding speed was 2.5m/min.