Provided is a liquid processing nozzle that eliminates the effects of biased flows, thus being able to produce an adequate cavitation effect, and, by extension, a microbubble-generating effect or gas dissolution efficiency. The liquid processing nozzle 1 is provided with: a nozzle body 2 having a liquid passage 3 formed therein； and a processing core CORE comprising a partition wall 8 that partitions the liquid passage 3 into an inflow chamber 6 on a liquid inlet 4 side and an outflow chamber 7 on a liquid outlet 5 side, a plurality of apertures 9 that are formed through the partition wall 8 and allow the inlet chamber 6 and the outlet chamber 7 to communicate with each other via separate passages, and protrusions 10 that protrude from the inner surface of the apertures 9 and are formed on the outer peripheral surface such that a plurality of ridge sections 11 and valley sections 12, which serve as high flow rate sections, alternately extend in the peripheral direction. The aspect ratio of the apertures 9, defined by L/de (where de represents the diameter of a circle equivalent to the total of the axial cross-section area of the apertures 9, and L represents the length of the apertures 9), is set to 3.5 or less； and in a projection on a plane orthogonal to the axis of the nozzle body 2, the smaller the distance T, which represents the distance from a reference point defined by the center position of the projection area of the partition wall 8 to the inner peripheral edge of the plurality of apertures, is than the inner diameter d of the apertures, the closer the apertures 9 are positioned.L'invention concerne une buse de traitement de liquide qui élimine les effets d'écoulements sollicités et est ainsi capable de produire un effet de cavitation adéquat, et par extension, un effet de génération de micro-bulles ou une efficacité de dissolution de gaz. La buse de traitement de liquide (1) comprend: un corps de buse (2) comprenant un passage de liquide (3) formé en son
