A dialogue system for a vehicle may include: a storage configured to store vehicle state information and driving environment information; an input processor configured to acquire an utterance from a user and to extract an action corresponding to the utterance when it is identified that the utterance includes user state information; a dialogue manger configured to acquire a parameter value of a condition determination parameter used to determine whether the action corresponding to the utterance is executable from the storage, to determine an action to be executed based on the parameter value of the condition determination parameter, and to acquire a parameter value of an action parameter used to execute the determined action from the storage; and a result processor configured to generate a response to execute the determined action using the acquired parameter value of the action parameter.