Jama Masjid Shahi Imam made the announcement tonight after a meeting of the moon-sighting committee, a senior official at the city's historic mosque said.
"The moon was not sighted today. So, that means the Eid will be celebrated on Saturday in Delhi and several other parts of the country," he was quoted by news agency PTI.
Eid-ul-Fitr, which marks the end of the fasting month of Ramzan, symbolises peace and brotherhood.
The festival is marked with feasts and the faithful offers prayers at mosques and idgahs to seek blessings of the divine.
On this day, people, especially children dress up in their traditional fineries to mark the festival that spreads the message of brotherhood and communal amity.