Baru died of an undisclosed ailment on Friday night. He was aged 60.
Mele Kyari, who succeeded Baru at NNPC, announced the death on Saturday morning.
“My brother, my friend and my mentor, Dr Maikanti Kachalla Baru, immediate past GMD of NNPC died late last night,” Kyari said on Twitter. “He was of exemplary character and disposition. May Allah forgive him and have mercy upon him.”