Hydroxymethylation of furfuryl alcohol with aqueous formaldehyde, yielding selectively 2,5-bis(hydroxymethyl)furan, has been carried out in the presence of various dealuminated H-form mordenites. The best results expressed in terms of both selectivity (greater than or equal to 95%) and conversion (greater than or equal to 70%) are obtained over H-MOR 100 catalyst (0.25 g) using a furfuryl alcohol/formaldehyde molar ratio of 0.009 after short reaction times (less than or equal to 30 min) and at low temperatures (313-327 K).