The objective of the study was to assess the role and challenges of militia in ensuring the local security in Tach Gayint woreda. Also, it aimed to assess whether militia strengthens or undermines state authority. Data were collected using questionnaire, interviews, FGD, Observation and document analysis. Data were analyzed using percentage and content analysis. The findings of the study reported: the incomplete activities of militia; their poor acceptances by the residents; and less satisfaction of the general public towards their role. Though there are few ethical militia members that play significant role in strengthening the security of the Woreda, large number of militia members were found threats to local security through their use arms for only their private purposes, establishing unlawful relationships with bandits, participating in illegal arms transfers, popping a bullet in a wrong place (unlawful) committing crime, getting drunkard, committing adultery and theft, violation of human and democratic rights, and using unnecessary forces during handling of wrong doers. Therefore, these factors were discovered as the main root causes for the failure of militia to play its significant role in ensuring local security. Also, these activities were found against duties and responsibilities of militia. Based on the findings, the militia members were challenged by poor motivation systems, poor coordination between kebele militia commander and woreda militia office employees and suspicion (mistrust) among themselves. Indeed, this urged the necessity of developing ethical guidelines and manuals to provide training to the militias. Especial attention should also be given for empowerment of women and the youth so that they can participate in decision making about security issues and ethics of militia. The regional government should develop motivation systems via providing rewards, incentives, and certificates to those ethical and hard worker militias so that their interest and commitment to serve the community through ensuring local security is maximized. Based on the findings, it is recommended that the regional government should take urgent solution to the security issues of the local community. Because, in the current scenario, large number of militia members are contributing their share to undermine local administrative (state) authority through their participation in different illegal activities. It is concluded; therefore, that the Amhara regional government needs to establish tight supervision mechanisms so that militia can contribute to ensure local security instead of challenging local administrative (state)authority through involvement in different illegal activities.