In order to reveal the interaction between nano-micro particles and clay minerals in drilling process，styrene，butyl acrylate and poly（ethylene glycol）monomethyl ether methacrylate macromonomer were used to prepared ether type polymer particles by emulsion polymerization method. The chemical structure and size distribution were determined by infrared spectrometer and laser particle size tester. The effect of particle on the performance of drilling fluids was studied and the function mechanism was discussed. The results showed that the polymer particle possessed the structural characteristic of ether bond groups. The particle size distribution was narrow in the range of 0.2—1 μm and the ratio of nano and micro particle was about 2∶8. Ether type nano-micro particles had good compatibility with drilling fluid. It could be used to control the filtration of polysulfide，polymer and APG clay-free drilling fluids at temperature as high as 130℃ and improve the quality of mud cake.