A simulated agent for liquid propellants was gelled efficiently and instantly at room temperature by modulating aggregate behaviors of a typical surfactant with the addition of a carboxylic salt in two polar solvent mixtures. An orthogonal test (three factors and four levels) was employed to investigate the factors affecting the rheological properties of the gels of the simulated agent. Results show that the significance of the factors affecting the mechanical strength of the gels follows the order of (1) the composition of the composite gelators (a surfactant and a carboxylic salt), (2) the composition of the mixture solvents, and (3) the temperature at which the gel had been prepared. However, the factors affecting the viscosity of the gel systems at higher shear rate (4355.0 s^-1) follows another order, that is (1) the composition of the mixture solvents, (2) the gel preparation temperature, and (3) the composition of composite gelators. Considering the results from frequency scan and those from orthogonal test, a gel from the simulated agent having high stabilities and low-viscosity at a high shear rate was obtained. In the gel formula, the molar ratio of the composite gelators, and the volume ratio of the mixture solvents are 2：1 and 1：3, respectively, and the total mass percentage of the composite gelators is 2.4%. Moreover, the dynamic yield value and the viscosity of the gel at higher shear rate are 794.3 Pa and 13.7 mPa·s, respectively.