The four new members will replace those set to step down April 20.
The outgoing members are Koh Seung-beom, Cho Dong-chul, Shin In-seok and Lee Il-houng.
A change of more than a majority of members may signal a shift in the way the central bank operates its monetary policy.
However, the observers say such a case will be highly unlikely, noting all new members will be nominated by different people.
The BOK board consists of both the governor and senior deputy governor of the central bank and five other members who are nominated by either the BOK governor, finance minister, Financial Services Commission chief or the head of the Korea Chamber of Commerce and Industry.
Such a nomination process is designed to prevent dominance.
Also to prevent a majority of board members stepping down at the same time, two of the four new members will have three-year terms instead of the usual four-year terms, according to the BOK.
In order to provide a buffer against shocks from the outbreak of the new coronavirus, the BOK has slashed its policy rate to a new record low of 0.75 percent, in its first emergency rate cut in more than a decade.
The central bank may deliver yet another rate reduction to help spur spending and boost economic growth.
The bank's next rate-setting meeting is slated for April 9. (Yonhap)