In the last few years, there has been a rise in interest in ride-hailing as a novel form of urban transportation and mobility service. This comprehensive literature analysis evaluates how ride-hailing services affect public road transportation in terms of traffic congestion, safety and security. The evaluation is grounded in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology, which includes a thorough search for pertinent studies, careful article screening and selection, data extraction, and quality assessment. This systematic literature review analyses and summarises data from 160 studies examining how ride-hailing services affected public road transportation. The literature review results indicated that ride-hailing services affect public road transportation positively and negatively, depending on various variables such as the regulatory environment, user behaviour, and service accessibility. The positives include greater environmental sustainability, lessening traffic congestion, and increased accessibility and comfort for riders. Nevertheless, the negatives comprise heightened competition among public transportation companies, decreased funding for public transit agencies, and perhaps even unfavourable consequences on ride-hailing drivers' working conditions. Based on the results of our literature review, we can conclude that there is a need for additional research to investigate the intricate relationships between ride-hailing services and public road transportation, as well as to develop suitable policy measures to minimise unfavourable effects and maximise the potential benefits of these ride-hailing services.