Abstract: Disclosed are an improved guide device capable of being easily replaced for damage, and a detector having the same. The guide device includes a first plate configured to have a plurality of grooves disposed in one surface thereof; and a second plate configured to be in contact with the first plate, wherein the second plate is in contact with the first plate to separate a plurality of channels, wherein the first plate is configured so that the plurality of microdroplets pass through any one of the plurality of channels, the fluid passes through channels facing each other among the plurality of flow channels, and the microdroplets are regularly spaced apart by the fluid that is discharged from the channels facing each other.