A MEMS resonator, comprising: a substrate; a moving structure suspended above said substrate and having its main extension in a horizontal plane (xy) formed by a first (x) and a second (y) horizontal axis which are orthogonal to one another, the structure comprising a first and a second flexing arm, parallel to one another and extending along the second horizontal axis (y), said first and second flexing arms being coupled at their respective ends by a first and a second transverse joining element, having an extension along the first horizontal axis (x), thus forming an internal window; a first electrode structure, positioned outside said window, capacitively coupled in said horizontal plane (xy) to the moving structure; wherein the first electrode structure comprises a first and a second outer electrode (20a, 20b), arranged facing and parallel to the first and second flexing arm (12a, 12b) respectively; a second electrode structure, positioned inside said window, capacitively coupled in said horizontal plane (xy) to the moving structure, wherein the second electrode structure comprises a first and a second inner electrode (21a, 21b) arranged inside the window, facing and parallel to the first and second flexing arm (12a, 12b) respectively; one of said first and second electrode structures (20, 21) operable to cause an oscillatory movement of said first and second flexing arm, in opposite directions along said first horizontal axis (x), at a corresponding resonance frequency, and the other of said first and second electrode structures (20, 21) operable to detect said oscillation; and a suspension structure, configured to suspend said moving structure above the substrate, characterized in that said suspension structure comprises a suspension arm extending inside said window, between a central portion of said first transverse joining element and a corresponding central portion of said second transverse joining elements, and an anchoring arrangement, coupled to said suspension arm and to said substrate, positioned centrally in said window near said second electrode structure. a substrate; a moving structure suspended above said substrate and having its main extension in a horizontal plane (xy) formed by a first (x) and a second (y) horizontal axis which are orthogonal to one another, the structure comprising a first and a second flexing arm, parallel to one another and extending along the second horizontal axis (y), said first and second flexing arms being coupled at their respective ends by a first and a second transverse joining element, having an extension along the first horizontal axis (x), thus forming an internal window; a first electrode structure, positioned outside said window, capacitively coupled in said horizontal plane (xy) to the moving structure; wherein the first electrode structure comprises a first and a second outer electrode (20a, 20b), arranged facing and parallel to the first and second flexing arm (12a, 12b) respectively; a second electrode structure, positioned inside said window, capacitively coupled in said horizontal plane (xy) to the moving structure, wherein the second electrode structure comprises a first and a second inner electrode (21a, 21b) arranged inside the window, facing and parallel to the first and second flexing arm (12a, 12b) respectively; one of said first and second electrode structures (20, 21) operable to cause an oscillatory movement of said first and second flexing arm, in opposite directions along said first horizontal axis (x), at a corresponding resonance frequency, and the other of said first and second electrode structures (20, 21) operable to detect said oscillation; and a suspension structure, configured to suspend said moving structure above the substrate, characterized in that said suspension structure comprises a suspension arm extending inside said window, between a central portion of said first transverse joining element and a corresponding central portion of said second transverse joining elements, and an anchoring arrangement, coupled to said suspension arm and to said substrate, positioned centrally in said window near said second electrode structure.