Khokar, who was nominated as president by the chief patron Prime Minister Nawaz Sharif earlier this month was elected at a special congress meeting of the PHF held in Islamabad.
"My foremost aim is to resurrect Pakistan hockey's image at home and abroad and for this I will explore all avenues to raise much funds for hockey and make PHF a financially stable institution," Khokar told the media after the meeting.
"The congress has accepted the resignation of Shahnaz Sheikh and appreciated his contribution to Pakistan hockey and team," Khokar said.
The resignation of Sheikh, a former Olympian, was on the cards after the national team failed to qualify for the Rio Olympics.
It is the first time that Pakistan hockey team will not appear in the Olympics, leading to swift action by the government which set up a probe committee to look into the causes of defeat and other ills and problems afflicting the sport in the country.