5-Hydroxymethylfurfural (HMF) is considered as a platform chemical derived from C6 sugars, which can be transformed into various important biochemicals and biofuels. The preparation of HMF in an efficient and green way is of great significance for its large scale production. Attapulgite modified by phosphoric acid (ATP-P) has been used to transform saccharides (fructose, glucose, inulin and starch) into HMF in a 2-butanol-water biphasic system with satisfactory results, in which HMF yields of 96.3% and 50.4% were obtained from fructose and starch, respectively. The amount of Brensted acid sites of ATP notably increases after modification by phosphoric acid, which endows ATP with a proper B/L ratio (Bronsted acid sites to Lewis acid sites) for HMF production. This B/L ratio is necessary because the production of HMF from saccharides is a multistep mechanism that involves isomerization catalyzed by Lewis acid sites and dehydration by 61 misted acid sites. Moreover, the catalyst provides good stability because the catalytic activity remained nearly unchanged after it was used 4 times. This work provides a green and economic alternative for biomass conversion using natural clays as catalysts. (C) 2019 Elsevier Ltd. All rights reserved.