Objective To study the expression of 4 circular RNA (circRNA) in peripheral blood mononuclear cells (PBMC) of patients with epilepsy and to predict its function by bioinformatics, so as to provide basis for exploring the pathogenesis of epilepsy. Methods From May 2020 to May 2021, 22 epilepsy patients were treated in the Department of Neurology of the First Affiliated Hospital of Baotou Medical College of Inner Mongolia University of Science and Technology, and 22 control group were selected. There were 13 males and 8 females in the epilepsy group, with an average age of (36.41±8.39)years. There were 11 males and 11 females in the control group, with an average age of (34.41±8.68) years. The expression levels of circRNA EFCAB2, C14orf159, PARG and TMEM39 in PBMC were detected by real-time fluorescence quantitative PCR, and their functions were predicted by bioinformatics. Results Compared with the control group, the relative expression of EFCAB2 and C14orf159 in PBMC of epileptic patients was 1.42±0.06 (t=29.41) and 1.31±0.03 (t=25.27), PARG and TMEM39 were not detected in peripheral blood PBMC. Bioinformatics analysis showed that three mirnas obtained by EFCAB2 were miR-6873-3p, miR-6739-3p and miR-7110-3p. Three mirnas were obtained by C14orf159: miR-1180-3p, miR-6501-3p, and miR-3622b-5p. The seizure-related genes were predicted by TargetScan database. EFCAB2: miR-6873-3p met the requirements of 11 downstream genes. A total of 7 downstream genes of miR-6739-3p met the requirements.A total of 14 downstream genes were eligible for miR-7110-3p and a total of 9 downstream genes were eligible for miR-6501-3p. A total of 14 downstream genes were eligible for miR-3622B-5p.miR-1180-3p has a total of 1 downstream genes that meet the requirements. Conclusions Studies have shown that two circrnas, EFCAB2 and C14orf159, may be important biological markers of epilepsy. Through bioinformatics analysis, these two circrnas may act as "molecular sponges" to regulate epilepsy. EFCAB2 has the potential to act as a "molecular sponge" for miR-6873-3p and miR-7110-3p, and it was found that miR-6873-3p and miR-7110-3 share a common downstream target gene MAP1B-which plays a role in epilepsy by regulating voltage-gated sodium channels. C14orf159 can act as a molecular sponge for miR-6501-3p to regulate the expression of CCL3 and play a role in epilepsy.