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A 2 × 2 microfiber knot resonator (MKR) coupler is demonstrated. The hybrid device is obtained by forming a knot within the coupling region of a microfiber coupler with a 50:50 splitting ratio.The microfiber coupler is successfully fabricated by laterally fusing and tapering two optical fibers using a flame-brushing technique.The coupler has an overlapping length of 40mm with a uniform waist of around 5 μm.With an MKR structure,the coupler produces a resonant response at both output ports.The free spectral range of the output spectrum from both ports is obtained at 0.2 nm at a knot diameter of 260 μm.The resonance extinction ratio of the device varies from 2 to 6dB while the calculated Q factor and finesse are ～25646 and 3.3,respectively,at both output ports.