The invention discloses a single-point supporting film rolling mill capable of displaying a roller gap. The film rolling mill comprises a frame type bracket, an upper roller, an upper roller bearing, an upper roller bearing block, a lower roller, a lower roller bearing, a lower roller bearing block, an inverted prismatic table supporting seat, a roller gap change on-line sensing display, a slant wedge set, an oil cylinder, a driven gear pair, a driven gear, a main gear, a speed reduction motor, a base, an upper seat beam, a lower seat beam, a bolt, a bottom bolt, and the like. Compared with the prior art, the film rolling mill solves the problem of imbalance of supporting points at two ends, thus the problem of nonuniform thickness of a rolled lithium ion battery pole piece is solved; and the gap between two rollers can be displayed on line, and gap changes can be instantly corrected in a film rolling process so that the problem that the compactedness of the rolled roll lithium ion battery pole piece is nonuniform is solved.