PCDA (Pentacosadiynoic Acid) monomers were successfully embedded in PCL (Poly ?-Caprolactone) polymer matrix by electrospinning process for the first time. The resultant EFM (Electrospun Fibers Mat) was photo-polymerized under 254 nm UV light that enables colorimetric detection of fake gasoline. Results revealed that the fake gasoline develops a red color mat within 5 sec. FE-SEM images showed that the fake gasoline treatment dissolved the PCL EFM that give access to interact with PDA polymer. The proposed litmus-type sensor based on PCL-PDA EFM is highly sensitive to fake gasoline and can be fabricated easily