An organic electroluminescent (OEL) display panel has improved lifetime and better display quality with a reduced amount of residual solvent on the isolating walls of the OEL panel. The organic electroluminescent display panel includes: a substrate, a plurality of first electrodes positioned on the substrate, a plurality of polyimide-isolating walls that are parallel to each other, an organic electroluminescent layer positioned on portions of the first electrodes that are not covered by the polyimide-isolating walls, and a plurality of second electrodes positioned on the organic electroluminescent layer. The cross-section of the polyimide-isolating walls has a reverse-trapezoid shape. The polyimide-isolating walls have electric, thermal and mechanical stability, thereby improving luminescent stability and lifetime of the organic electroluminescent display panel which, in turn, improves the stability and lifetime of the organic electroluminescent display panel.