With the aim to explore the gelling rules, the stability and the textural properties of inulin under acidic conditions, and the effect of pH value on the gelatin were studied at different concentrations of inulin. The experimental results show that the gelling ability decreases and the gelling time increases with the decrease of pH value. The volumetric gel index increases with inulin content increase and decreases with pH value decrease. When pH value decreases to 1，gelatin can’t be formed even the concentration of inulin solution is high as 60%. The water retention of gelatin increases with the increase of inulin content and the increase extent becomes weak as pH value decreases. The water retention of 60% gelatin increases by 9.4%, 5.75% and 5.47% compared with that of 40% gelatin at pH value 7, 5 and 3, respectively. The higher the inulin content is, the stabler the stability of gelatin to pH value is. The acid hydrolysis rates of 40% inulin gelatin are 1.35 and 2.97 times higher than that of 50% and 60% gelatins when the pH value equals 3 and the hydrolysis time is 24h. Texture profile analysis shows that pH value has positive correlations with the hardness, strength, adhesiveness, cohesiveness and gumminess of gelatin. Differential scanning calorimetry analysis shows that the freezable water content of 50% gelatin increases to the maximum, 26.0%, when pH value decreases from 7.0 to 3.0.