Abstract: China plans to explore the near Earth asteroid 2016H03 and collect samples to return to the ground, the physical properties, chemical composition, and mineral composition of the 2016H03 will be provided scientific date for the origin and evolution of asteroids and the solar system processes. For the first near-earth asteroid sampling and encapsulation mission, sealing tecchnology is used to maintain the original state of the sample and ensure the scientific value of samples, a structure of double rubber double radial seal is designed, and some experimentation is carried out. Experiment result shows that the leakage rate of the seal was less than 5×10⁻⁶ Pa·m³·s⁻¹ and the sealing tecchnology can be used to seal near-earth asteroid sample.