A synchronous dual-liquid syringe is provided, including a first and a second injection devices, both respectively including a barrel and a plunger a connecting device, having a main tubing and a branch tubing an infusion tubing, provided between the barrel of the first injection device and the branch tubing and an inner and an outer needle assemblies, respectively including an inner needle and an outer needle. The inner needle passes through the main tubing and enters inside of the outer needle. The inner and outer needles constitute an outer flow channel. The inner needle surrounds to form an inner flow channel. The tip of inner needle does not exceed the tip of outer needle. As such, the user can easily push the two plungers to simultaneously inject two liquids into a mixing space or into a patient for mixing, without the risk of mixed medicament stuck inside the needle.一種雙液同步注射器,包括第一、第二注射裝置、連接裝置、輸液管、內針頭組及外針頭組。第一、第二注射裝置分別包括針筒及推桿。連接裝置包括主管路及分支管路。輸液管設於第一注射裝置的針筒與分支管路之間。內、外針頭組分別包括內、外針頭,內針頭延伸穿過主管路的主通道且延伸入外針頭的內部,內、外針頭共同構成外流道,內針頭圍構內流道,內針頭的注射端不超過外針頭的注射端。藉此,使用者能夠輕易地推動二推桿將兩種液體同步注射到混合空間或者病患體內進行混合,完全沒有混合藥劑卡在針頭內部的風險,混合效果容易掌控。10‧‧‧第一注射裝置11‧‧‧針筒12‧‧‧推桿20‧‧‧第二注射裝置21‧‧‧針筒22‧‧‧推桿30‧‧‧連接裝置31‧‧‧主管路312‧‧‧本體3131‧‧‧第一段314‧‧‧第二端部32‧‧‧分支管路33‧‧‧套筒34‧‧‧防滲漏結構40‧‧‧輸液管50‧‧‧內針頭組51‧‧‧結合座52‧‧‧內針頭60‧‧‧外針頭組61‧‧‧結合座62‧‧‧外針頭70‧‧‧座體80‧‧‧套管
