Sharma, who represents Raipur rural seat, was administered the oath by Governor Shekhar Dutt in a function held at Raj Bhawan here.
Sharma has been elected to Assembly six times. He had become member of the undivided Madhya Pradesh Assembly in 1985.
He was appointed as pro-tem Speaker by virtue of his seniority as per the convention.
Sharma will administer the oath of office to all newly-elected members of the House during the five-day session beginning on January 6.
On January 7, the Governor will address the House and discussion on the vote of thanks on his speech would take place, Sharma said.
In recently-concluded Assembly polls, Raman Singh steered BJP to the third consecutive win by defeating rival Congress.