The Hyaluronic Acid Fresh Sun Serum by Isntree has received positive feedback for its lightweight and hydrating properties, which can be beneficial for oily skin. Many reviewers have noted that it absorbs well without leaving a greasy or heavy feeling, making it suitable for daily use. However, some users with oily skin have mentioned that it may feel slightly rich or start to feel oily after extended wear. It's important to note that individual experiences may vary, and it's recommended to apply it in thin layers and possibly mix it with other products for better compatibility.