In order to explore the fertilization uniformity of water-fertilizer integrated micro-sprinkler belt in the field and its influencing factors, the concentration of fertilizer solution along the direction of micro-sprinkler belt and perpendicular to it were analyzed by measuring the concentration of fertilizer solution with two belt lengths under four working pressures of the bow. The results showed that the laying length of the micro-sprinkler belt had little influence on the uniformity of the concentration of fertilizer, but with the decrease of the pressure along the belt, the amount of fertilizer would decrease with the decrease of the irrigation water. The concentration of the fertilizer solution perpendicular to the direction of the belt changed gently near the belt, whereas the concentration of the fertilizer solution decreased slightly along the direction of the belt. It is found that different laying lengths have different optimal working pressures of the bow. When the laying length is 20 m, the working pressure of the bow is about 40 kPa, whereas when the laying length is 40m, the working pressure of the bow is about 28 kPa, and the concentration of fertilizer liquid changes gently. The combination of micro-sprinkler belt and proportional fertilizer pump used in the integrated irrigation of water and fertilizer can enhance the uniformity of fertilizer liquid. It is suggested that reasonable allocation and appropriate working pressure of the bow should be applied in practical use.