This invention relates to a plane fluorescent lamp structure including a first base plate, a second base plate, at least an baffle structure, a fluorescent material and a light emitting gas, in which, the second plate is corresponding to the first to form a closed space, the baffle structure divides the space into multiple luminescence cavities, a channel structure passing through the baffles connects the cavities and divides the adjacent cavities into a first cavity and a second cavity, the fluorescent material is set in the inside walls of the multiple cavities and the luminescence gas is filled in the cavities, in which, the ratio of the length and the section area of the channel is defined to be the first coefficient, the ratio of the cavity length and the section area of the first cavity is the second coefficient, the ratio of the length and section area of a second cavity is the third coefficient, the three coefficients have a proportion relation. |