The invention provides a blowing-carding electrical control system and a control method. The blowing-carding electrical control system comprises a bale plucker, an opener, a multi-bin cotton blending machine, a scutcher, a cotton conveying pipeline, a carding machine, a fan, a metal-fire detector, a dust removal machine, sensors and a control system and is characterized in that the control system comprises a central controller and a human-machine interface, the sensors comprise a bale plucker traveling speed sensor, a picking depth sensor, cotton blending pipeline pressure sensors, cotton blending bin level sensors, a cotton blending machine inclined screen speed sensor, a cotton blending machine flat screen speed sensor and cotton conveying pipeline pressure sensors, the signal output ends of the sensors are connected with the signal input end of a central controllor, and the controllers of the bale plucker, the opener, the multi-bin cotton blending machine and the scutcher are connected with the central controller respectively. The automation control of the online detection and the real-time adjustment of the blowing-carding system can be achieved, situations such as multi-bin useless running, overlarge fluctuation of cotton storage amount, unsteady rear stage cotton conveying and frequent start stop can be avoided, and smooth cotton supply and continuous and even sheet cotton output can be guaranteed.