The present invention relates to a drug injection device which has a compact structure and can enable convenient and safe injection of a plurality of drugs in accordance with the use. The present invention provides a drug injection device comprising: a cover； a first tube which is placed inside the cover and through which a first drug flows； a storage unit which is placed inside the cover and accommodates a second drug that flows out by means of pressure from outside； a second tube which is connected to both sides of the storage unit, respectively, and through which the second drug, flowing out, can flow； a pressing unit which is movably placed on one side of the cover and enables applying or releasing of pressure to and from the storage unit in accordance with the movement； and a control unit which is placed on the other side of the cover and is for controlling the movement of the pressing unit in accordance with the operation thereof. The present invention has a compact structure and enables convenient use thereof simply by means of connection to a drug supply unit. And the present invention can be conveniently operated, thereby enabling quick injection of drugs in accordance with the state of a patient. In addition, risk of injection on the basis of the use of drugs can efficiently be prevented.La présente invention concerne un dispositif d'injection de médicaments qui présente une structure compacte et peut permettre une injection pratique et sécurisée d'une pluralité de médicaments en fonction de l'utilisation. La présente invention concerne un dispositif d'injection de médicaments comportant: un capot； un premier tube qui est placé à l'intérieur du capot et à travers lequel s'écoule un premier médicament； une unité de stockage qui est placée à l'intérieur du capot et contient un second médicament qui s'écoule vers l'extérieur au moyen d'une pression extérieure； un second tube qui est relié aux deux côtés de l'unité de stockage, respectivement, et à travers leq
