Objective To explore the current status and influencing factors of opportunistic infections in Crohn disease. Methods Data on demographic characteristics, disease features, treatment regimens and laboratory results of 369 patients with Crohn disease admitted to a tertiary grade A hospital in Shanghai from January 2020 to August 2024 were retrospectively collected. Univariate analysis and multivariate Logistic regression were employed to identify the influencing factors of opportunistic infections in Crohn disease. Results The incidence of opportunistic infections in patients with Crohn disease was 32.25%. Specifically, the incidence rates of viral infections, bacterial infections, and multiple infections were 16%, 12.2%, and 3.8%, respectively. Multivariate Logistic regression analysis showed that low disease activity [odds ratio (OR)=3.22, 95% CI: 1.18−8.81, P=0.023], moderate disease activity (OR=7.16, 95% CI: 1.88−27.31, P=0.004), albumin < 30 g/L (OR=4.99, 95% CI: 2.04−12.18, P < 0.001), and C-reactive protein > 10 mg/L (OR=3.70, 95% CI: 1.27−10.78, P=0.016) were independent risk factors for Crohn disease complicated with Epstein-Barr virus infection. A Charlson comorbidity index score of 1 (OR=5.01, 95% CI: 1.51−16.60, P=0.008), albumin < 30 g/L (OR=3.45, 95% CI: 1.23−9.72, P=0.019), and C-reactive protein >10 mg/L (OR=13.06, 95% CI: 2.46−69.40, P=0.003) were independent risk factors for Crohn disease complicated with latent mycobacterium tuberculosis infection. C-reactive protein >10 mg/L (OR=20.41, 95% CI: 2.13−195.52, P=0.009) was an independent risk factor for Crohn disease complicated with multiple infections. Conclusions Disease activity, co-existing chronic diseases, hypoalbuminemia, and elevated C-reactive protein levels are predictive factors for opportunistic infections in patients with Crohn disease. Active prevention as well as early diagnosis and treatment should be implemented for these patients at risk.