The invention relates to a new tyre vertical pressure distribution function, an algorithm and a test system. The new tyre vertical pressure distribution comprises steps that, S1, an average pressure module is determined; S2, inner vertical grounding blotting length is acquired; S3, a bias coefficient is acquired; and S4, the new tyre vertical pressure distribution function is constructed. Through the function and the algorithm, problems of relatively low precision and can-not-be-excellently-reflected tyre rolling direction existing in a traditional tyre vertical pressure distribution function employing a parabola function are solved, in combination with the average pressure module, the inner vertical grounding blotting length and the bias coefficient, the new tyre vertical pressure distribution function capable of realizing simple and accurate computation is constructed, and thereby the vertical pressure distribution situations are conveniently tested.