The invention discloses a multipoint spot welding machine for a cellular board capable of guaranteeing the uniformity of a forced convection flow field. According to the multipoint spot welding machine for the cellular board capable of guaranteeing the uniformity of the forced convection flow field, a welding head is arranged on a welding head driving mechanism, the cellular board is formed by welding semi-cellular steel strips, a welded piece positioning mechanism is provided with a positioning mechanism guide rod and a positioning mechanism guide sleeve, the positioning mechanism guide rod is in sliding fit with the positioning mechanism guide sleeve, the welding head driving mechanism is provided with a driving mechanism guide rod and a driving mechanism guide sleeve, the driving mechanism guide rod is in sliding fit with the driving mechanism guide sleeve, and the positioning mechanism guide rod is perpendicular to the driving mechanism guide rod. According to the multipoint spot welding machine for the cellular board capable of guaranteeing the uniformity of the forced convection flow field, two linear bearing sliding systems and one manual sliding plate system are used for achieving connection of the semi-cellular steel strips through multipoint spot welding, the production efficiency of the machine is high, and the spot-welded positions are uniform and attractive in appearance; the problem that a negative electrode support for small-interval and high-density welding spots is prone to deformation is solved; the uniformity of the welding spots is guaranteed, and the pre-pressures of the welding spots can be adjusted slightly by adjusting the extension length of the spot welding head.