This observational retrospective study was conducted on patients with epilepsy (PWE) in China who had at least one dose of COVID-19 vaccine and it investigated the safety of vaccination by analyzing changes in epileptic seizures and their influencing factors. Consecutive PWE who were followed up in the epilepsy clinic between June 2021 and May 2022 were enrolled. Data on vaccine type, demographic information, clinical characteristics of epilepsy, and treatment were collected through a questionnaire survey and retrospectively analyzed. PWE were divided into a stable seizure group and a worsening seizure group based on seizure episodes at least 90 days after the first vaccine dose. A total of 79 PWE were included. After vaccination, 14 patients (17.7%) had worsening seizures, 92.9% of whom had an increased seizure frequency. Compared with patients in the stable seizure group, patients in the worsening seizure group had significant differences in baseline monthly seizure frequency (P = .012), improper antiseizure medication (ASM) administration (P = .003) and a disrupted sleep routine (P = .016). Multivariate logistic regression analysis showed that improper ASM administration (OR 6.186, 95% confidence interval [CI] 1.312–29.170; p = .021) and a disrupted sleep routine (OR 6.326, 95% CI 1.326–30.174; p = .021) were significantly associated with seizure worsening. In short, COVID-19 vaccination is safe for PWE, and only those with poor seizure control have the possibility of seizure exacerbation after COVID-19 vaccination. The vaccination per se does not represent a major influencing factor, but the improper use of ASMs and a disrupted sleep routine may be correlated with seizure aggravation after vaccination.