The ignition of both deal and fir blocks were tested with a bench-scale flashover test apparatus. Tests results showed that the bench-scale flashover test apparatus could offer a test environment similar to the true fire environment and tests executed with the apparatus had good repeatable property. Based on the cone calorimeter test results, a new ignition criterion of wood was presented in the paper. Ignition time of wood block in the bench-scale flashover test apparatus were calculated with the tested average temperature of the upper smoke layer and the new ignition criterion. The calculation results showed that the new approach was facile and available for the purpose of forecasting the ignition time of wood blocks in the bench-scale flashover test apparatus.