Provided is an automatic fashion outfit composition and recommendation method including a user's query item about fashion being input to a vendor item DB and the vendor item DB extracting the class and vector of the query item and transmitting the same to a reference DB, the reference DB retrieving and extracting similar items having vectors that are similar to the vector of the query item and then retrieving and extracting reference fashion outfit including the similar items, the reference DB extracting reference items included in the reference fashion outfit, computing the class and vector of each of the reference items, and transmitting the same to the vendor item DB, the vendor item DB retrieving and extracting recommended items having vectors that are similar to the vectors of the reference items, and the vendor item DB combining the query item and the recommended items to compose recommended fashion outfit and sorting and transmitting the recommended fashion outfit to a user.