The fine needle aspiration (FNA) cytologic findings in a rare case of bilateral diffuse sclerosing carcinoma of the thyroid are described. Along with a generally papillary architecture, the FNA biopsy smears showed a number of features not usually seen in thyroid carcinomas: psammoma bodies, an abundance of squamous metaplasia and a dense inflammatory component. The FNA diagnosis was multifocal papillary carcinoma with squamous metaplasia; histopathologic examination made the final diagnosis.