In this work, monomer miniemulsion of 3-[tris(trimethylsilyoxy)silyl]propylmeth- acrylate(TRIS) was prepared by a method of mechanical stirring with ultrasonic homogenization, with DNS525 and DNS500 as composite emulsifier(mass ratio of DNS525 and DNS500 was 1:1). The effects of mechanical stirring time, ultrasonic homogenization time, dosage of emulsifier, and mass ratio of TRIS and water on performance, stability and particle diameter of TRIS monomer miniemulsion were studied. The optimum condition was obtained as follows: mechanical stirring time was 60min, ultrasonic homogenization time was 15 min, dosage of emulsifier was 6%, mass ratio of TRIS and water was 2:3. The polymer miniemulsion obtained under this condition was white with blue light, homogeneous liquid. The gel content was 0.62%, the conversion rate was 98.32%, average particle diameter was 226.4nm, and the value of polydispersity index was 0.143.