The purpose of this qualitative paper was to examine the linguistic make-up of grave threats through the use of pragma-linguistic analysis. Specifically, this study aimed to look into the syntactic, semantic and pragmatic features of grave threats in Philippine decided cases. The results revealed that the most commonly used sentence in expressing grave threats were exclamatory sentences and the most commonly used sentence according to structure were simple when expressing a direct threat and complex when expressing conditional threat. The act of threatening was considered under commissive and directive illocutionary acts particularly threatening and challenging since the speaker committed an act of doing something under a certain condition. Specifically, this commissive illocutionary force involved coercion wherein a course of action was proposed to avoid a negative response. In the case in which a particular speech act was not completely described in grammar, formal features of the utterance used in carrying out the act was quite directly tied to its accomplishment. In the case of grave threat, the speaker’s intention in making the utterance and recognition by the addressee of that intention under the conditions of utterance clearly played an important role. The results of this study may be beneficial to various entities that are indirectly and directly involved in investigating language crimes particularly that of grave threats.