Prime Minister Yousuf Raza Gilani appealed to the world community to extend a helping hand to tackle the calamity.
The country is coping with its worst ever floods that have left over 1,600 people dead and affected over 14 million people.
The government called off all festivities and there was no ceremony at the Aiwan-e-Sadr, the official residence of Pakistan President Asif Ali Zardari.
According to sources, Zardari was scheduled to spend the day with flood victims in Punjab and Khyber-Pakhtunkhwa provinces.
Government officials were also reluctant to organize functions and participate in festivities as they visited flood-hit areas.
The Pakistan army also cancelled its celebrations, donating the fund it would have spent on the day's activities to flood victims instead, said sources.
"We are celebrating our 64th Independence Day at a time when the country is up against many challenges, the chief being rehabilitation of flood victims, the fight against terrorism, the struggling economy and ensuring political stability," said Gillani.