The invention relates to a production method of a wide plate blank production method with improvedfor improving the acid-soluble boron content. The method comprises the following steps of performing converter melting; performing catch carbon practicehigh carbon pulling operation; stabilizing the C hit rate according to the upper limit control in the C target range; reducing nitrogen absorptionsuction; after steel discharging, entering enabling materials to enter into an argon blowing station; performing an LF refining work procedure; maintaining the constant temperature, constant liquid surface and constant pulling speed in the continuous casting process; maintaining 20 to 30 DEG C low overheat degree in the casting process; performing full protection casting; using an argon sealing long water gap by a bag packnozzle for a large ladle; using an immersed water gapnozzle for a middle ladlepack; using crystallizer electromagnetic stirring and tail end electromagnetic stirring in the casting process in the continuous casting process; performing continuous casting blank offline slow cooling; reducing for alleviating composition segregation in the cast condensing process. The method solves the technical problems of low boron-containing steel yield, instable B content, low acid-soluble boron ratio and cost increase in the prior art; the existing advanced production equipment is used;the goal aim of controlling nitrogen and oxygen is achieved through reinforcing the control on each work procedure control; the acid-soluble boron content is improved; the uniformity is improved; thegoal aim of producing wide plate blanks with good low-power quality is reached.