The optative usage during Koine period is commonly known to be fading. However, authors like Josephus and Philo have used quite a bit of optative in their writings in comparison with others of the same period. This study intends to compare Josephus and Philo with some written works in Koine period including LXX, OT Apocryphal (Wisdom, Sirach, Judith, Tobit, 1 Maccabees, 2 Maccabees, 4 Maccabees, and Psalms of Solomon), New Testament, and Apostolic Fathers on their usage of optative mood. The method of study will start from comparing the major syntactical use of optative between Classical Greek and Hellenistic Greek. Afterwards, comparison among writers in Koine period will be done on their optative expression of: 1) wish or prayer; 2) condition; 3) indirect speech. The purposes of current study want to explore the syntax on the optative usage in some of the works of Josephus and Philo, and to bring enrichment of understanding of the optative mood in Koine period.