This study aims to investigate the differences in the realization of request speech act between the IEL (Indonesian English Learners) and the AES (Australian English-Native Speakers), as well as explain the factors influencing these distinctions. The descriptive-qualitative method and discourse completion task (DCT) were used to obtain data in various contexts. The results showed that the realization of request speech act of the IEL and AES were different based on the following, (1) Form of Speech, as observed in the use of the main and supporting actions. This indicated that the IEL and AES used indirect and direct speech acts, respectively, and (2) Different Speech Strategies, as observed in the mode of sentences and request strategies. This proved that the IEL often used interrogative sentences, with the AES using declarative sentences when seeking permission from work superiors, and (3) Differences in the use of semantic formulas, where the IEL used attracters and honorifics more than the AES. This revealed that the linguistic and non-linguistic factors influenced the occurrences of these differences.