The idea of Rahmatan Lil ‘Alamin is predominantly derived from Surah al-Anbiya, verse 107. The lexicon “rahmat” connotes various interpretations that include Islam and al-Qur’an. Meanwhile, al- Qur’an was revealed to Prophet Muhammad (p.b.u.h.) which contains principles and injunctions as a proclamation and guideline to mankind. This revelation intends to preserve the public interests while preventing from harm. The objective of this study is to analyse the appraisal of forensic science application within the context of justice. This study aims to appraise the nexus between concept Rahmatan Lil ‘Alamin and al-Maqāṣid al-Sharīʿah. This qualitative study used documentary research method in collecting primary and secondary data. The data have been analysed using content analysis method by adapting inductive reasoning. The appraisal of forensic science application within the context of justice indicates numbers of findings; the forensic science application is permissible in Islam. It also denotes forensic science have been long practiced since the prophet era, where numbers of forensic methods have been applied to uphold the justice at that time. Apart from that, there was also a nexus between the concept of Rahmatan Lil ‘Alamin and al-Maqāṣid al-Sharīʿah. The relation can be seen from the common purpose of both concepts which are preserving the public interest and preventing harm. Therefore, the application of forensic science shall be the meeting point between forensic science application, concept Rahmatan Lil ‘Alamin and al-Maqāṣid al-Sharīʿah. It bridges the gap between science and shariah. This study contributes in building the integration between science and shariah elements through application of forensic science and the concept of Rahmatan Lil ‘Alamin. This study has also indirectly proved the concept of al-shumūl, al-thabāt, and al-murūnah in Islamic teachings that encompassed various fields of knowledge. This study suggests more research to be conducted in regards to the application of fiqh forensics in various field.