A Micro-Electro-Mechanical System (MEMS) device, comprising: a substrate, a packaging component provided on the substrate and a MEMS component provided inside the packaging component and on the substrate; the device further comprises a sealing structure, wherein the sealing structure is provided on the substrate and/or the packaging component; and wherein the sealing structure is provided to prevent an external small molecular substance from contacting with the MEMS component, wherein the packaging component comprises a first packaging layer and a second packaging layer, wherein the first packaging layer is provided at a location on the substrate without contacting with the MEMS component, and the first packaging layer surrounds the MEMS component; the second packaging layer is provided on a surface of the first packaging layer far away from the substrate and above a surface of the MEMS component far away from the substrate; and the first packaging layer is connected with the second packaging layer together, wherein the second packaging layer and the MEMS component are not in contact with each other, characterized by, the sealing structure comprises a first sealing structure comprising only irregular protrusions and depressions, and wherein the first sealing structure is provided between the first packaging layer and the second packaging layer; and in the presence of the first sealing structure, the first packaging layer and the second packaging layer are connected with each other tightly with first packaging layer in contact with the second packaging layer through the first sealing structure, the first sealing structure is provided at a location of the first packaging layer facing the second packaging layer. wherein the sealing structure is provided on the substrate and/or the packaging component; and wherein the sealing structure is provided to prevent an external small molecular substance from contacting with the MEMS component, wherein the packaging component comprises a first packaging layer and a second packaging layer, wherein the first packaging layer is provided at a location on the substrate without contacting with the MEMS component, and the first packaging layer surrounds the MEMS component; the second packaging layer is provided on a surface of the first packaging layer far away from the substrate and above a surface of the MEMS component far away from the substrate; and the first packaging layer is connected with the second packaging layer together, wherein the second packaging layer and the MEMS component are not in contact with each other, characterized by, the sealing structure comprises a first sealing structure comprising only irregular protrusions and depressions, and wherein the first sealing structure is provided between the first packaging layer and the second packaging layer; and in the presence of the first sealing structure, the first packaging layer and the second packaging layer are connected with each other tightly with first packaging layer in contact with the second packaging layer through the first sealing structure, the first sealing structure is provided at a location of the first packaging layer facing the second packaging layer.