The design, fabrication and evaluation of single and mechanically coupled capacitive silicon nanomechanical resonators is reported. The structure of resonators is fabricated on a silicon on insulator wafer and transferred to a Tempax glass substrate by anodic bonding. A finite element method simulation has been conducted to investigate the vibration modes of the resonators. Single beam resonator with a length of 21.3 μm, a width of 500 nm, a thickness of 5 μm and the capacitive gap size of about 300 nm shows a nonlinear response. The amplitude of frequency response increases as the frequency is swept upward, and then suddenly jumps to a lower value. The mechanically coupled capacitive silicon nanomechanical resonator with a number of 100 individual beams above is successfully fabricated. Some resonant peaks can be observed, which shows that most nanomechanical resonators are mechanically coupled and synchronised. A mechanical resonance at a high frequency of ∼7.2 MHz in flexural mode has been detected. A small motional resistance of 1.2 kω has been achieved by the mechanical coupling.