Rinse the dried osmanthus flowers quickly under cold water to remove dust.
Add the water and flowers to a small pot. Bring to a gentle simmer.
Turn off the heat, cover, and let the flowers steep for 10 minutes.
Strain the liquid if you want a clearer jelly. You can keep the flowers if you like texture.
Add the sugar to the warm liquid and stir until fully dissolved.
Sprinkle in the agar agar powder and stir well so there are no lumps.
Bring the mixture back to a boil. Let it boil for 1 full minute to activate the agar.
Pour the hot liquid into molds or a shallow dish.
Let it cool at room temperature, then chill in the fridge for 1 hour until fully set.
Cut into cubes and serve cold.
