The effect of Flammulina velutipes soluble polysaccharide (FVSP) on the gel properties of myofibrillar protein (MP) was investigated. Mixed gels were prepared by adding different concentrations (0.5%, 1%, and 1.5%) of FVSP to MP. The effects of different FVSP concentrations on MP gel properties were compared by measuring the whiteness values, gel strength, water holding capacity (WHC), Fourier infrared transform spectrum, and thermal denaturation temperature. Optical microscopy and scanning electron microscopy were also conducted. Results showed that FVSP addition increased the gel strength and WHC compared with those of the control. FVSP also enhanced gel formation and MP structure stability and produced a 3D gel matrix with high G' and G" values. Maximum gel strength and WHC were obtained at 1.5% FVSP concentration. Microscopy images showed that FVSP filled in the gel matrix and promoted a homogeneous and stable structure. In conclusion, FVSP addition substantially improved the gel properties of MP. This work provides scientific basis for the future application of FVSP in meat products.