Chief Justice Tassaduq Hussain Jillani approved the names of three judges -- Justice Anwar Zaheer Jamali, Justice Iqbal Hameedur Rahman and Justice Ejaz Afzal -- for the commission.
Prime Minister Nawaz Sharif had on Sunday announced a judicial commission would be formed which would probe the attack on Mir in Karachi on Saturday.
According to a spokesman for the Prime Minister House, the commission would be given three-weeks time to submit its report.
The spokesman added that Rs 1 crore reward had also been announced for those who will help identify the attackers.
Meanwhile, Sharif today visited Mir, who is recuperating at a hospital in Karachi.
Defence Minister Khawaja Asif, Sindh Chief Minister Qaim Ali Shah and Sindh Governor Ishratul Ibad accompanied the prime minister.
Speaking to the media, Sharif said that an investigation into the attack on Mir was underway and no stone would be left unturned.
Mir, 47, who faced threats from multiple quarters including the Taliban, was on Saturday shot at in Karachi by four unidentified gunmen.
Mir's brother has accused "elements in the ISI" of orchestrating the attack on him, a charge denied by the military.
Image: A policeman shows the media a bullet hole in the door of a car which belongs to journalist Hamid Mir, at a local hospital in Karachi
Photograph: Athar Hussain/Reuters