The invention discloses a plant seedling nozzle adjustment device for an agricultural sprinkler. The plant seedling nozzle adjustment device comprises a bottom tube, wherein a bottom frame is arranged on one end of the bottom tube, a support tube is arranged on the other end of the bottom tube, a side tube is arranged on the support tube, a side frame is arranged on the bottom frame, and a fixed plate is arranged between the ends of the side frame and the side tube; an adjustment tube is arranged on the lower part of the side tube, an adjustment tank is arranged in an axial position of the adjustment tube, an operating tube is arranged on the upper part of the adjustment tube, adjustable brackets are arranged on both sides of the operating tube, the adjustment tube is installed on the support tube by virtue of a rotary shaft, an operating rod is arranged above the bottom tube, one end of the operating rod is connected with the adjustable brackets, the other end of the operating rod is arranged on the end of a support frame, a V-shaped frame is arranged on the end of the support frame, and grips are arranged on both sides of the end of the V-shaped frame. The plant seedling nozzle adjustment device for the agricultural sprinkler can be used for conveniently sprinkling plant seedlings on farmlands.