The burning velocities of rich hydrogen-oxygen mixtures at atmospheric pressure have been studied experimentally as a function of the equivalence ratio phi and the initial temperature T-0 in the range 1 less than or equal to phi less than or equal to 5.05 and 120 K less than or equal to T-0 less than or equal to 300 K, respectively. A conical flame is stabilized at the exit of a cylindrical tube (Bunsen-type burner) and the burning velocity is determined by Gouy＇s method as the ratio between the volumetric flow rate at the exit of the burner and the total flame area. The latter is assumed to be that derived from the flame Schlieren photograph. A systematic analysis of the results describes the burning velocity as a function of the equivalence ratio and of both unburned gas and adiabatic combustion temperatures in the range of the low unburned gas temperatures. A unique value of the activation energy E summarizes the sensitivity of the mass burning rate to the combustion temperature, whatever the equivalence ratio. The analysis involves comparisons with other experimental and numerical work.