A new borate [H2EG][B7O10(OH)3](1) based on [B14O20(OH)6]4-polyborate anions has been solvothermally synthesized in the presence of H2EG as a template(EG = ethylene glycol).The structure was determined by single-crystal X-ray diffraction and further characterized by FTIR,elemental analysis and thermogravimetric analysis.Compound 1 crystallizes in the triclinic system,space group P,with a = 8.5095(4),b = 8.8694(4),c = 10.0756(4) ,α = 95.094(2),β = 96.936(2),γ = 116.844(2)°,V = 664.66(5) 3.The structure of 1 consists of [B14O20(OH)6]4-moiety,which could be regarded as the largest isolated polyborate anion so far.The anions are interlinked via hydrogen bonding to form a 3D supramolecular network,whereas the diprotonated [H2EG]2+ are filled in the free space of inorganic borate network and interact with the inorganic framework by extensive hydrogen bonds.It is noteworthy that the EG acts not only as a solvent,but also as a template. A new borate [H2EG] [B7O10 (OH) 3] (1) based on [B14O20 (OH) 6] 4-polyborate anions has been solvothermally synthesized in the presence of H2EG as a template (EG = ethylene glycol) was determined by single-crystal X-ray diffraction and further characterized by FTIR, elemental analysis and thermogravimetric analysis. Compound 1 crystallizes in the triclinic system, space group P, with a = 8.5095 (4), b = 8.8694 c = 10.0756 (4) α, α = 95.094 (2), β = 96.936 (2), γ = 116.844 (2) °, V = 664.66 53.The structure of 1 consists of [B14O20 (OH) 6] 4-moiety, which could be regarded as the largest isolated polyborate anion so far. The anions are interlinked via hydrogen bonding to form a 3D supramolecular network, whereas the diprotonated [H2EG] 2+ are filled in the free space of inorganic borate network and interact with the inorganic framework by extensive hydrogen bonds.It is noteworthy that the EG acts not only as a solvent, but also as a template.