A needle structure for injecting a filler and monitoring a blood backflow situation simultaneously includes a needle, a housing and a partitioning member. The needle includes a needle chamber and a needle opening connected to the needle chamber. The housing includes a housing chamber and a housing opening connected to the housing chamber, and the housing chamber is connected to the needle chamber to form a needle housing chamber. The partitioning member is disposed in the needle housing chamber. The needle housing chamber is separated into a first chamber and a second chamber by the partitioning member. The needle opening is separated into an injection opening and a blood backflow opening by the partitioning member. The first chamber is connected to the injection opening, and the blood backflow opening and the housing opening are connected by the second chamber.
