What is transfer function? All Questions › Category: Control System › What is transfer function? 0 Vote Up Vote Down Chetan Shidling Staff asked 5 years ago I need short information. 1 Answers 0 Vote Up Vote Down Chetan Shidling Staff answered 5 years ago The transfer function of a linear time-invariant system is defined as the ratio of Laplace transform of the output to the Laplace transform of the input under the assumption that all initial conditions are zero.