The present work aims to show that dielectric constant measurement is a new and deep method for discriminating fountain pen inks. To achieve this goal the dielectric constant for the identification of fountain pen ink has been studied. The data was obtained by designing and setting up an alternative current (AC), Function Generator, and Oscilloscope for measuring the resistance of each fountain pen ink sample. The measurements were performed in the frequency range between 1 Hz and 3 MHz at room temperature. Then, resistance measurements were used to the calculate dielectric constant. To support the result, as a conventional method, TLC-IA (image analysis) was applied to the same samples to discriminate these samples based on the intensity profile of red, green, and blue (RGB) by using the software PyCharm Community 2024.1.1. The results from each method supported each other. This new method allowed us to identify the different fountain pen inks with the obtained results.