A needle structure for injecting fillers is disclosed. The needle structure includes a needle body, a housing body and a separator. The needle body includes a needle chamber and a needle opening. The needle chamber is connected to the needle opening. The needle body is connected to the housing body. The housing body includes a housing chamber and a hole. The housing chamber is connected to the needle chamber to form a needle cavity. The separator is disposed in the needle cavity. The needle cavity is separated to form a first chamber and a second chamber by the separator. The needle opening has two openings. One is injection opening and the other one is bleeding-check opening. The first chamber has injecting fillers and is connected to the injection opening. The second chamber is connected to the bleeding-check opening and the hole. We have natural blood pressure inside our veins and arteries. If the needle opening is inside the vessel, we can see the phenomenon of blood reflow in the transparent camber to confirm the position of the neddle is inside a vessel. Therefore, the needle structure use transparency of the second chamber to confirm the bleeding situation. The needle structure can prevent blood clots and effectively improve the safety of surgery.本發明係一種針頭結構，其包含針體、殼體及分隔件。針體之針體腔室連接針口。殼體連接針體且包含殼體腔室與開孔，針體腔室連通殼體腔室而形成針頭空腔。分隔件將針頭空腔分隔出第一腔室與第二腔室，第一腔室與第二腔室彼此隔離。分隔件將針口分隔出注射口與回血口，第一腔室裝有填充物且連通注射口，第二腔室連接回血口與開孔。由於人體本身的血管不論動脈靜脈都有自然的壓力存在，在注射到血管時會有回血的現象，藉此利用第二腔室之透明性與開孔來確認回血狀況，能使注射者在施打時避免打到血管而造成血管栓塞，進而提高手術安全性。
