Provided is a substrate processing apparatus including a load-lock chamber; a transfer chamber connected to the load-lock chamber; and one or more processing chambers connected to the transfer chamber. The transfer chamber includes a transfer arm that transfers a substrate between the load-lock chamber and the one or more processing chambers, the load-lock chamber includes a plurality of load-lock stations for accommodating a plurality of substrates as a matrix of m×n. According to the substrate processing apparatus, a time taken to transfer substrates may be reduced greatly, and productivity may be improved.