BackgroundTo report a case in which silicone oil accidentally entered Berger’s space (BS) after vitrectomy and to explore the effective treatments and possible etiological mechanisms.Case presentationA 68-year-old male underwent vitrectomy and silicone oil injection for the treatment of retinal detachment (RD) in the right eye. Six months later, we noticed an unexpected lens-like round translucent substance located behind the posterior lens capsule and diagnosed it as BS filled by silicone oil. Subsequently, we conducted vitrectomy and the drainage of the silicone oil in BS in the second surgery. A 3-month follow-up showed significant anatomic recovery and visual recovery.ConclusionsOur case report presents a patient with silicone oil entering BS after vitrectomy and provides photographs of BS from a relatively unique perspective. Furthermore, we illustrate the surgical treatment procedure and reveal the possible etiology and prevention method of silicon oil entering BS, which will provide good insights for clinical diagnosis and treatment.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12886-023-03035-8.