NEEDLE ASSEMBLY

According to the present disclosure, there is provided a needle assembly comprising:a needle support portion in which a hollow needle through which a medicinal solution can flow is supported;a movable needle cover portion that is movable in an opening portion of a casing such that an injection-side end portion of the medicinal solution of the needle protrudes outward in use;a tubular portion arranged on the needle support portion and partially abuttable with the movable needle cover portion; anda biasing portion configured to bias the movable needle cover portion in a direction opposite to one direction along with movement of the movable needle cover portion in the one direction,the needle support portion, the movable needle cover portion, the tubular portion, and the biasing portion being each configured to be at least partially accommodated in the casing having the opening portion,wherein at least the movable needle cover portion abuts on the tubular portion by the movement of the movable needle cover portion in the one direction to axially rotate from a predetermined position before movement to another position, so that the movable needle cover portion after the axial rotation is movable in the opposite direction by the biasing portion, andwherein the movable needle cover portion after the axial rotation, which has completed the movement in the opposite direction, can be locked to the casing.