The pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been basically under control in China since March 2020，but the import of domestic SARS-CoV-2 have begun to increase. This study reported the first case of asymptomatic SARS-CoV-2 infection imported from Spain into Sichuan Province, China, on March 11, 2020. The infected male had a body temperature of 37.5°C, normal blood oxygen saturation levels, and a computed tomography (CT) examination showed that his lungs had no shadows. However, a throat swab from the subject tested positive for SARS-CoV-2 using qPCR assay. In this study, we conducted transcriptome sequencing on respiratory throat swabs from the subject and found that the dominant SARS-CoV-2 sequence (Gene Bank ID: MW301121) was a spike protein D614G mutant strain, which is currently popular throughout world. We downloaded and analyzed SARS-CoV-2 sequences collected from cases in China and Spain for comparison and tracing purposes.