Singh drove down to Rashtrapati Bhawan for a noon meeting with Mukherjee. The meeting lasted half an hour," a PMO official said.
Officials described the meeting as a courtesy call with nothing on the agenda.
This is the first meeting between Singh and Mukherjee since he assumed the office of President on Wednesday.
Vice President Hamid Ansari, Defence Minister AK Antony, Governors of several states, Leader of the Opposition in the Lok Sabha Sushma Swaraj were among those who had called on Mukherjee yesterday.