The invention discloses a vision-based shaping and defective product detection method. The method comprises the steps that first, electronic components are trimmed, wherein in the trimming process, apneumatic unit provides power, and an electronic component pin bending cylinder is made to move first through processing of the electromagnetic valve; pins are bent according to the dimensional requirement for width; after bending is completed, an electronic component pin shearing cylinder is started to shear the pins; and after trimming is completed, the electronic components are inserted into acircuit board. Through the method, convenience is brought to trimming work and statistical work of three types of electronic components with different dimensions by an operator; and when a trimmed product is inserted into the circuit board, subsequent inspection also can be performed.