During the pandemic, quarantine hotel workers face a higher risk of infection while they host quarantine guests from overseas. This study’s aim is to gain an understanding of the knowledge, attitudes, and practices (KAP) of quarantine hotel workers in China. A total of 170 participants took part in a cross-sectional survey to assess the KAP of quarantine hotel workers in China, during the COVID-19 pandemic. The chi-square test, independent t-test, one-way analysis of variance (ANOVA), descriptive analysis, and binary logistic regression were used to examine the sociodemographic factors associated with KAP levels during the COVID-19 pandemic. The results show that 62.41% have good knowledge, 94.7% have a positive attitude towards COVID-19, but only 78.2% have good practices. Most quarantine hotel workers (95.3%) are confident that COVID-19 will be successfully controlled and that China is handling the COVID-19 crisis well (98.8%). Most quarantine hotel workers are also taking personal precautions, such as avoiding crowds (80.6%) and wearing facemasks (97.6%). The results evidence that quarantine hotel workers in China have acquired the necessary knowledge, positive attitudes and proactive practices in response to the COVID-19 pandemic. The results of this study can provide a reference for quarantine hotel workers and their targeted education and intervention.