The sensitivity and specificity of magnified endoscopic features for differentiating follicular lymphoma from other diseases with duodenal whitish lesions have never been investigated. Here we compared the magnified endoscopic features of duodenal follicular lymphoma with those of other whitish lesions. We retrospectively reviewed the cases of patients with follicular lymphoma (n＝9), lymphangiectasia (n＝7), adenoma (n＝10), duodenitis (n＝4), erosion (n＝1), lymphangioma (n＝1), and hyperplastic polyp (n＝1). The magnified features of the nine follicular lymphomas included enlarged villi (n＝8), dilated microvessels (n＝5), and opaque white spots of various sizes (n＝9). The lymphangiectasias showed enlarged villi, dilated microvessels, and white spots, but the sizes of the white spots were relatively homogeneous and their margin was clear. Observation of the adenoma and duodenitis revealed only whitish villi. Although the lymphangioma was indistinguishable from the follicular lymphomas by magnified features, it was easily diagnosed based on the macroscopic morphology. In conclusion, magnified endoscopic features, in combination with macroscopic features, are useful for differentiating follicular lymphomas from other duodenal diseases presenting whitish lesions.