Methods This study included 102 patients who underwent cardiac surgery at Beijing Chaoyang Hospital, from May 2018 to December 2019. Combination of neuropsychological scales were used to test patients' cognition at the timepoints of 1 d preoperatively and 7 d postoperatively. Perioperative neurocognitive disorder (PND) was diagnosed according to the Z‑score method. Patients were divided into the group with patients who have PND (group P, 33 cases) and the group with patients without PND (group NP, 69 cases) according to according to with or without PND. General characteristics, tumor necrosis factor‑α (TNF‑α)、interleukin (IL)‑1、IL‑6、S100β、malonic dialdehyde (MDA)、total antioxidant capacity (T‑AOC) concentrations were collected at the timepoints of 5 min preoperatively (T0), at the end of surgery (T1), 1 d postoperatively (T2) and 3 d postoperatively (T3). Results The PND occurred in 33 of 102 patients (32.4%). The mean age of patients in the group P was higher than that in the group NP while the mean years of education were shorter than in the group NP (P<0.05). IL‑6, MDA and S100β concentrations were higher in the group P than those values in the group NP at T2 (P<0.05), while T‑AOC concentrations were lower than those values in the group NP (P<0.05). S100β concentrations was higher in the group P than that in the group NP at T3 (P<0.05). No other statistically significant difference was found between the two groups (P>0.05). Conclusions This study found a high incidence of PND after cardiac surgery. In addition, the occurrence of PND was accompanied by increased inflammatory response and oxidative stress response.