According to the present invention, a safety cover is mounted on a syringe needle hub in one side of a syringe, and a user is prevented from being damaged by a syringe needle. A check valve structure of a filter structure disposed in one side of the syringe is improved, so an injection is discharged only through a discharging pathway when the injection is certainly fed and discharged. Thus, foreign materials included in the injection are certainly filtered. By improving the safety cover and the filter structure, stability is enhanced. To this end, a filter structure (300) of the present invention comprises: a sealing ring (310) having a penetration hole (312) formed in the center thereof a first valve (320) having the sealing ring (310) formed in one end thereof, having a center including an insertion hole (322) and one or more first feeding holes (324) for feeding an injection, and having one or more first discharging holes (326) formed in the outer circumferential side thereof to have a pathway for discharging the injection a second valve (330) disposed in one end of the first valve (320), having one or more second feeding holes (334) formed in the center thereof, and having one or more second discharging holes (336) formed in the outer circumferential side thereof to have a pathway for discharging an injection a filter sheet (340) disposed in one end of the second valve (330), having a third feeding hole (342) formed in the center thereof, and filtering foreign materials included in an injection when the injection is discharged and a check valve (350) supported on the first valve (320), guiding the inflow of an injection, and preventing the injection from being leaked to an injection pathway when the injection is discharged.COPYRIGHT KIPO 2017본 발명은 주사기 일측에 주사바늘허브에 안전커버를 장착시켜 주사바늘에 의해 상해를 입는 것을 방지하고, 상기 주사기의 일측에 구성되는 필터구조체의 체크밸브 구조를 개선시켜 주사액의 확고한 유입 및 배출시 주사액이 배출경로를 통해서만 배출되어 상기 주사액에 포함된 이물질이 확실하게 여과되도록 구성함으로써, 상기 안전커버 및 필터구조체의 개선으로 안정성을 향상시키는 데 그 목적이 있고, 이를 위해 본
