Ignition experiments of methane and air mixture in low equivalence ratio were carried out in a shock tube. Ignition delay in different working conditions was obtained through transient pressure signal and OH emission measurement. The experiment results were compared with the calculation based on detailed methane oxidation mechanism. Analysis results indicate that: there is a linear relationship between the logarithm of ignition delay and the reciprocal of temperature; ignition delay decreases with the reduction of methane concentration; the apparent activation energy of experiment results agrees well with the simulation of detailed mechanism.