Bionic artificial muscle is a popular research topic nowadays. When electroactuated gel-based bionic artificial muscle generates output force, it often appears "output force tremor behavior", which seriously affects the output force characteristics and driving stability of bionic artificial muscle. Therefore, based on the three influencing factors of lyophilization process (addition amount of glycerin, crosslinking concentration of calcium chloride and freezing temperature), a comparative study on the output force characteristics and tremor behavior of sodium alginate gel-based bionic artificial muscle was conducted, and the improvement mechanism of their output force characteristics was deeply analyzed. The results show that when the moisturizer glycerin is 3 mL, the maximum output force of the bionic artificial muscle is 5.78 m·N. When the crosslinking concentration of calcium chloride is 1%, the maximum output force is 6.09 m·N. When the freezing temperature is －60 ℃, the maximum output force is 6.76 m·N, the oscillation amplitude of output force is 0.4 m·N, which is about 1.29 times of 0 mL glycerol, and 0.3 times of 2% calcium chloride. The output force tremor frequency is 1 time, which is about 0.3 times of that at the crosslinking concentration of 3 mL glycerol and 5% calcium chloride. Therefore, the freezing temperature of the freeze-drying process is the most critical factor affecting the output force0 characteristics and tremor behavior of th bionic artificial muscle, and the optimal freezing temperature is －60 ℃.