A network port cover module, comprising: a plurality of modules configured to be inserted into and coupled to a network port of a network device, the plurality of modules being configured to be locked and coupled together or separated from each other, and configured to be locked and coupled to or unlocked and separated from the network port according to a locked and coupled state or an unlocked and separated state of the plurality of modules, wherein the plurality of modules comprises a locking module and a pattern module that are configured to be locked and coupled together or unlocked and separated from each other, and to be coupled to the network port in a locked and coupled state, wherein the locking module includes, a locking module body configured to be inserted into the network port, a main-locking portion that is provided to be elastically deformed at an outside of the locking module body and brought into contact with and latched on a locking step of the network port, an interfered portion connected to the main-locking portion, and a sub-locking portion provided to be elastically deformed at the locking module body, and the pattern module includes, a front wall having a shape corresponding to an open front of the network port and a keyhole, a horizontal connecting portion horizontally extending from the front wall and having a pattern groove at a lower surface thereof to be connected to the keyhole, an interfering portion extending from the outside of the horizontal connecting portion and interfering with the interfered portion when the pattern module reciprocally moves relative to the locking module, thereby elastically deforming the main-locking portion, wherein when the locking module and the pattern module are coupled together, a locking step provided at a lower surface of the horizontal connecting portion is latched on the sub-locking portion and the locking module and the pattern module are maintained in a locked and coupled state, and the sub-locking portion is configured to be interfered with and separated from the locking step by an unlocking tool inserted into the keyhole. a plurality of modules configured to be inserted into and coupled to a network port of a network device, the plurality of modules being configured to be locked and coupled together or separated from each other, and configured to be locked and coupled to or unlocked and separated from the network port according to a locked and coupled state or an unlocked and separated state of the plurality of modules, wherein the plurality of modules comprises a locking module and a pattern module that are configured to be locked and coupled together or unlocked and separated from each other, and to be coupled to the network port in a locked and coupled state, wherein the locking module includes, a locking module body configured to be inserted into the network port, a main-locking portion that is provided to be elastically deformed at an outside of the locking module body and brought into contact with and latched on a locking step of the network port, an interfered portion connected to the main-locking portion, and a sub-locking portion provided to be elastically deformed at the locking module body, and the pattern module includes, a front wall having a shape corresponding to an open front of the network port and a keyhole, a horizontal connecting portion horizontally extending from the front wall and having a pattern groove at a lower surface thereof to be connected to the keyhole, an interfering portion extending from the outside of the horizontal connecting portion and interfering with the interfered portion when the pattern module reciprocally moves relative to the locking module, thereby elastically deforming the main-locking portion, wherein when the locking module and the pattern module are coupled together, a locking step provided at a lower surface of the horizontal connecting portion is latched on the sub-locking portion and the locking module and the pattern module are maintained in a locked and coupled state, and the sub-locking portion is configured to be interfered with and separated from the locking step by an unlocking tool inserted into the keyhole.