β-Yb 2 Si 2 O 7 powders were synthesized by a sol–gel method using ytterbium nitrate and tetraethyl orthosilicate as starting materials. The thermal history, influence of composition and calcining temperature on phase evolution of the gel were investigated using TG–DTA, FTIR and X-ray diffraction. Amorphous Yb 2 Si 2 O 7 formed below 950°C and a low-temperature phase (α-Yb 2 Si 2 O 7 ) was detected in powders calcined at 1000°C and 1100°C. Well crystalline β-Yb 2 Si 2 O 7 powders were obtained after calcining the xerogel at 1200°C for 2h. The average particle size of the powders calcined at 1200°C was ∼300nm. The crystallite size determined from both TEM and FWHM of XRD reflections was ∼60nm. Lattice parameters of β-Yb 2 Si 2 O 7 determined by Rietveld method were a=6.80053Å, b=8.87508Å, c=4.70740Å and β=101.984°. Atomic positions of β-Yb 2 Si 2 O 7 were identified as Yb(0.5, 0.80548, 0),Si(0.74150, 0.5, 0.42936), O(1) (0.5, 0.5, 0.5), O(2) (0.89831, 0.5, 0.75248), O(3) (0.74229, 0.65022, 0.18086).