An injection needle assembly includes a needle tube, a needle hub configured to hold the needle tube, a protector, a biasing member, and a restriction mechanism. The restriction mechanism is configured such that, after the protector has moved from the first position to the second position and has further returned from the second position to the first position, the restriction member restricts the protector from moving from the first position to the second position again. At least a portion of the biasing member is disposed on a needle tip side of the restriction mechanism in the axial direction.
