According to Disney Canon novel Tarkin by James Luceno, the Emperor used it as Imperial Palace.
BRIGHT-SIDE CORUSCANT air-traffic control directed the Carrion Spike to the Imperial Palace, and there into a courtyard landing field that was large enough to accommodate Victory- and Venator-class Star Destroyers. As repulsors eased the ship down through the busy skyways and into the court, Tarkin realized that the Emperor’s current residence had once been the headquarters for the Jedi—though practically all that remained of the Order’s elegant Temple complex was its copse of five skyscraping spires, now the pinnacle of a sprawling amalgam of blockish edifaces with sloping façades. ("Tarkin" by James Luceno, Chapter "Imperial Center")
The reason for that wasn't simply political - it was Sith related.
The two of them were in Sidious’s lair, a small rock-walled enclosure beneath the deepest of the Palace’s several sublevels that had once been an ancient Sith shrine. That the Jedi had raised their Temple over the shrine had for a thousand years been one of the most closely guarded secrets of those Sith Lords who had perpetuated and implemented the revenge strategy of the Jedi Order’s founders.
The Temple was heavily renovated, except for the Galactic Map
One of the few areas of the former Jedi Temple that had not undergone renovation was the holographic galactic map, an enormous globular representation of the galaxy located mid-level in what had been the Jedi Council spire. The Order had used the map to keep track of its far-flung members; now it served to identify trouble spots in the Emperor’s realm.
The Emperor had consented to allowing the members of his Ruling Council to confer with