Dominated by the great stone staircase leading to the balcony of the mezzanine floor and to the upper floors, the entrance hall is characterised by a sober and elegant style. 

The high ceiling, with its beams in polychrome wood, and the decorative frieze running all around dampen the austerity of the stone walls and confer unity to the hall.  

On the left wall is a huge sandstone baroque coat of arms of the Republic which used to decorate the façade of the old Government Building; on the right, under the great staircase, is a bronze bust of Giosuè Carducci by Tullo Golfarelli from Cesena, in memory of the eminent poet who, on 30 September 1894, made the inaugural speech for the new Building.

Besides the various memorial tablets dedicated to eminent San Marino citizens and foreign people, along the great staircase are two 16th century crossbows, the last remains of the original and fruitful local production. 

The two doors opposite to the entrance lead to the Offices of the Institutional Secretariat and to the Hall of the Audiences, where the Captains Regent receive their important guests and periodically also San Marino citizens.