Retinoblastoma-associated orbital cellulitis is a well-recognized clinical entity. Inflammation of orbital soft tissues can clinically mimic extraocular tumor invasion, potentially affecting patient management decisions. Magnetic resonance imaging (MRI) is an established modality for tumor staging and assessment of extraocular spread in advanced intraocular retinoblastoma. As far as we are aware, MRI findings in retinoblastoma-associated orbital inflammation have not been reported in the literature. Herein, we have described the MRI features of the orbit in retinoblastoma-associated cellulitis, and its role in differentiating inflammation from extraocular tumor invasion.