This systematic review examines the use of heat maps for weapon detection, an important aspect given the growing need for security. A comprehensive search was conducted in academic databases, resulting in the retrieval of 35 relevant articles published between 2017 and 2023. The findings indicate increasing interest in the field, especially in 2023 as new research continues to emerge. Key technologies utilized include deep learning, thermal image processing, and object detection. These works provide valuable tools associated with their real-world implementation. The recommendations for future work include improving evaluation methods, incorporating more scenarios and diverse users for testing, and optimizing algorithms. This review highlights the potential importance of heat maps in enhancing weapon detection systems and security. This emerging field, which combines computer vision, deep learning, and thermal imaging, identifies opportunities for future research.