As the conventional self-priming pump cannot satisfy the requirement of quick aerofluxus, a novel self-priming pump with distinct structure and the extraordinary self-priming mechanism was designed to afford promising opportunities for emergency water delivery. Meanwhile, to obtain the optimal profile of the blade, nine blades with different thickness distribution were systematically investigated based on computational fluid dynamics, and in order to benchmark the numerical calculation, the relevant external characteristic test was conducted. According to the results, spatial structure of boundary-layer separation bubble (BLSB) was displayed clearly by employing the new space coordinate system, which can not only trigger the hydraulic loss, but also give rise to the blockage of the passage. Additionally, the amplitude of pressure fluctuation on the blades initially decreases and subsequently rises with the flow rate increases, and the minimum amplitude was obtained under design flow rate. Furthermore, compared with the pressure fluctuation, induced noise and hydraulic characteristic of the blades with different thickness distribution, the blades with thickness distribution of 3-6-6 from inlet to the outlet are superior to the other blades obviously. Therefore, it reflects that the thickness distribution of the blade exerts vital influences on the performance of the self-priming pump, and this research could provide reference for designing the thickness distribution of the blades.