An experimental study of the flame response in a turbulent premixed combustor has been conducted in order to investigate mechanisms for combustion instabilities in a lean premixed gas turbine combustor. A lab-scale combustor and mixing section system were fabricated to measure the flame transfer function. Measurements are made of the velocity fluctuation in the nozzle using hot wire anemometry and of the heat release fluctuation in the combustor using chemiluminescence emission. The results show that the flame transfer functions are greatly dependent on the modulation frequency as well as operating conditions such as equivalence ratio. Flame dynamics can be generalized as a function of Strouhal number which is a ratio of flame length to modulation wave length.