Fucosylated oligosaccharides have important biological functions as well as an excellent antiviral activity. A novel α 1–2-fucosyltransferase (α 2FT) from Treponema primitia (Tp2FT) was cloned and expressed in Escherichia coli BL21(DE3) and purified as an N-His-tagged fusion protein (His-Tp2FT). Mass spectrometry was carried out to identify the products of enzymatic reaction. The Tp2FT exhibited strict acceptor substrate specificity for type 1 structure (Galβ1-3GlcNAc)-containing glycans. It might be a promising emzyme for the chemo-enzymatic synthesis of lacto-N-fucopentaose I (LNFP I), which is one of the important fucosylated oligosaccharides. In this study, different in vitro experiments were used to study the biological activities of LNFP I. It could reduce the concentrations of inflammatory cytokines and effectively inhibit the synthesis of enterovirus 71 proliferation. LNFP I was an inhibitor of enterovirus 71 in the early stages of infection, it can used in infant nutrition and might provide a new drug for hand foot mouth disease.