In this thesis the time-optimal control in linear time-invariant system with time-delay is investigated by applying the method of maximum principle. It is shown under some assumptions that anoptimal control is a piecewise constant function of time. Theorems on the existence and uniquenessof the optimal control are established. A brief discussion on an essential characteristic of the optimal feedback controller is also given and it is shown that the optimal controller should have a delayelement which gives the same amount of delay to the detected system variables as that of thecontrolled object.