The utility model provides a formula sowing mechanism is inhaled to needle, belonging to the field of agricultural machines, including frame and setting vacuum pump above that, driving motor, little sprocket, turning arm axle subassembly, the guide arm fixed axle, the camshaft subassembly, big sprocket, inhale kind of row's subassembly, first branch subassembly, second branch subassembly, plant the box, the aspiration channel, the intraductal intracavity portion of plenum in the subassembly is arranged to the effect downdraught kind of vacuum pump forms the negative pressure, the camshaft rotates in the driving motor driving cam axle subassembly, and wave through axle subassembly swing of cam drive turning arm and branch. The guide arm is fixed epaxial guide arm and is inhaled the plenum pipe in kind of row's combination and inhale kind of pipe and under the combined action of turning arm, branch, slide and spring, accomplish the whole seed metering process of inhaling. The utility model relates to a formula sowing mechanism is inhaled to needle adopts air -suction type to get kind of a principle, is fit for using in the mechanized live operation process of chinese -medicinal material, satisfies that chinese -medicinal material seed particle diameter is little, the characteristics and the single seed essence of light in weight, out -of -shape are broadcast, the agronomy requirement of little plant spacing, narrow row distance.