A system and method for providing a voice assistant service for text including an anaphor are provided. A method, performed by an electronic device, of providing a voice assistant service includes: obtaining first text generated from a first input, detecting a target word within the first text and generating common information related to the detected target word, using a first natural language understanding (NLU) model, obtaining second text generated from a second input, inputting the common information and the second text to a second NLU model, detecting an anaphor included in the second text and outputting an intent and a parameter, based on common information corresponding to the detected anaphor, using the second NLU model, and generating response information related to the intent and the parameter.