One kind of antireflection (AR) coating based on terahertz metamaterial with a stand-up structure is designed, which utilizing stand-up double split ring resonators (SRRs) to suppress the reflection in the terahertz range. The minimum reflectivity of AR coating is 0.001 and the band width is 0.45 THz when the reflectivity is below 0.1. The operating mechanism of this metamaterial antireflection coating is analyzed,the effects of the distance between the two split rings and the thickness of the polymer substrate on the performances of the metamaterial AR coating are investigated, and the performance comparison with that of the single SRR AR coating is conducted. The numerical simulation and analysis results show that the designed metamaterial AR coating has an excellent broadband reflection inhibition characteristic and a large production-parameter-tolerance characteristic.