Diversion acid fracturing is one of the effective measures to increase production of carbonate reservoir. Importantly, the key of this technology lies in the temporary plugging agent. However, the existing acid fracturing with temporary plugging agents are of poor acid resistance, complicated removal process, and high cost. Aiming at solving those problems, a micro-expansion temporary plugging agent (WDS) for acid fracturing was prepared through aqueous radical polymerization in this study. The degradation performance, temporary plugging performance, and reservoir damage of the WDS were studied, and it was applied in field construction. The results showed that it was first micro-expanded and then degraded in different solutions. The complete degradation time of the WDS reduced from 78 h to 45 h with the rising temperature from 70 ℃ to 120 ℃. The complete degradation time reduced from 75 h to 48 h with the rising concentration of HCl from 3% to 20%. According to the results of displacement experiment, with the increase of the injection, the temporary plugging pressure increased, and the time to reach the maximum temporary plugging pressure reduced. And with the increase of the fracture width, the temporary plugging pressure decreased, and the time to reach the maximum temporary plugging pressure increased. In addition, the WDS was less harmful to the core, and the permeability recovery value of cores of more than 90%. Furthermore, the field application results indicated that the construction pressure increased by 10 MPa after adding the WDS, and the effect of temporary plugging was remarkable. In conclusion, the WDS can be completely degraded under the conditions of temperature, acid, and salinity, and the effect of temporary plugging is remarkable. It has a good application prospect in diverting acid fracturing.