Microring-resonator filters were fabricated based On Silicon on Insulator (SOI) nano-wire waveguide, adopting Electron-Beam photolithography (EBL) and Inductive-Coupled-Plasma (ICP) etching technology, etc. The cross-section size of the strip waveguides were (350～500 nm)×220 nm, respectively, and the bending radius of the microring was around 5 μm. The measured results show that performance of devices are much better with waveguide width 450 nm, the free spectral range (FSR) is 16.8 nm, and extinction ratio (ER) around the wavelength 1 550 nm is 22.1 dB. After thermally tuned, the tuning bandwidth reaches 4.8 nm, and the tuning efficient is 0.12 nm/℃. Meanwhile, multi-channel filters were fabricated and studied based on single-ring and double-ring. After experiments, some conclusions were drawn: crosstalk exists in the signal transmission in multi-channel filters, mainly among different transmission channels, and the crosstalk is fairly distinct when there are signals input to add ports.