AbstractAim:Conjunctival squamous cell carcinoma (SCC) is a rare tumour of the ocular region and microscopic radical surgical is difficult. There are no single guidelines for therapeutic management and the role of radiation therapy is not clearly defined although conventionally photon or electron beams are used. Proton beam radiotherapy (PBRT) is a new option for a conservative approach and allows good sparing of the organs at risk.Materials and methods:After surgical resection, we collected 15 cases treated at our institution with PBRT. The dose delivered was between 48 and 60 Gy relative biological effectiveness (RBE), with fractions of 12–15 Gy RBE.Results:After an average period of 48 months, the patients achieved excellent disease control (overall survival and disease-free survival: 86·6%), with minimal acute and late toxicity.Findings:In this work, we present our experience on the use of PBRT technique in SCC treatment. A larger sample of patients is needed to draw conclusions about the impact of this treatment on disease recurrence and overall survival.