The Judd-Ofelt intensity parameter Ωt of a novel Er3+ doped high silica glass was calculated. The large values of Ω2,6 (Ω2=8.15×10-20,Ω6=1.22×10-20) indicate that the local structure of Er3+ has higher asymmetry and lower covalency than other oxide glasses. McCumber theory was used to calculate the stimulated emission cross section of 4I13/2→4I15/2 transition, the result was 0.51pm2. Despite the Er3+-doped concentration in high silica glass being about ten times greater than that in silica fiber, its fluorescence lifetime and quantum efficiency were 6.0ms and 66.0%， respectively. This novel Er3+-doped glass can be used in optical amplification and microchip laser.