This research explores the impact of doping silicene nanoribbons with arsenic atoms. The study focuses on two specific configurations: substituting a single silicon atom with an arsenic atom and replacing half the Si atoms in the unit cell. Using first principles theory, the system's electrical properties are investigated. The formation energies will be analyzed to identify the optimal structure when silicon atoms are replaced with arsenic atoms in all configurations. Furthermore, an external electric field of 0.3 eV/Å is applied to the system. This field causes alterations in the electronic properties, including changes to the bandgap. The introduction of an electric field results in significant modifications to the energy band structure, underscoring its potential for broad applications in materials science.