Anall-opticallight–control–lightfunctionalitywiththestructureofamicrofiberknotresonator(MKR)coatedwithtindisulfide(SnS2)nanosheetsisexperimentallydemonstrated.TheevanescentlightintheMKR[witharesonanceQof~59,000andanextinctionratio(ER)of~26dB]isexploitedtoenhancelight–matterinteractionbycoatingatwo-dimensionalmaterialSnS2nanosheetontoit.Thankstotheenhancedlight–matterinteractionandthestrongabsorptionpropertyofSnS2,thetransmittedopticalpowercanbetunedquasi-linearlywithanexternalvioletpumplightpower,whereatransmittedopticalpowervariationrateΔTwithrespecttothevioletlightpowerof~0.22dB∕mWisobtained.Inaddition,theMKRstructurepossessingmultipleresonancesenablesadirectexperimentaldemonstrationoftherelationshipbetweenresonanceproperties(suchasQandER),andtheobtainedΔTvariationratewithrespecttothevioletlightpower.ItverifiesexperimentallythatahigherresonanceQandalargerERcanleadtoahigherΔTvariationrate.Intermsoftheoperatingspeed,thisdevicerunsasfastas~3.2ms.Thiskindofall-opticallight–control–lightfunctionalstructuremayfindapplicationsinfutureall-opticalcircuitry,handheldfibersensors,etc.