【Objective】 To understand the epidemiological characteristics of COVID-19 in Shaanxi Province from December 9, 2021 to January 20, 2022, and analyze the factors influencing the interval from isolation to diagnosis. 【Methods】 We collected the data of local COVID-19 cases from December 9, 2021 to January 20, 2022 published on the official website of Health Commission of Shaanxi Province. Descriptive statistical method was used to analyze the epidemiological characteristics of COVID-19 in Shaanxi Province. Mann-Whitney U test and Kruskal-Wallis H test were used to compare the differences between groups. The unconditional Logistic regression model was applied to analyze the factors influencing the interval between isolation and diagnosis. 【Results】 The outbreak of COVID-19 in Shaanxi Province started on December 9, 2021 and ended on January 20, 2022. The overall change trend of the outbreak showed an "inverted V" shape. A total of 2,080 confirmed local cases were reported, and the main type of disease was mild, with an incidence rate of 5.26/100,000. Xi’an had the most cases, accounting for 98.69% of the total. The reported cases were mainly concentrated in people aged 21 to 55 years old, with a male-to-female sex ratio of 1.19∶1. The median interval from isolation to diagnosis was 3 days, the shortest interval being 0 day and the longest interval being 21 days. Unconditional Logistic regression model analysis showed that the way of finding cases was the factor influencing the interval from isolation to diagnosis. Compared with the way of isolation of the key population, the way of the nucleic acid screening could reduce the risk of late detection of confirmed cases by 89% (OR=0.11, 95% CI: 0.07-0.16). 【Conclusion】 The way of finding cases is the factor influencing the interval from isolation to diagnosis. In the face of the recent intensification of the spread of Omicron variant in mainland China, accurate and rapid identification and detection of confirmed cases can not only reduce the risk of the spread of the epidemic, but also endeavor more time and initiative for the treatment of patients, which is the key to curbing the spread of the epidemic.