We show the ability of the desired-dynamic-equations(DDE)based decentralized PID controller tuning method with its application to the ALSTOM gasifier benchmark control problem.The DDE-based PID controller tuning method was deduced from a kind of nonlinear adaptive controller,which behaves good tracking performance and robustness by using an extended state observer and DDE to estimate and compensate the uncertainty and disturbance.Moreover,the tunable parameters of DDE-based PID controller have explicit physical meanings.