The former prime minister was briefly released earlier this month for his wife's funeral.
Shehbaz, along with party leaders, met Nawaz in the office of the jail superintendent.
Another supporter in the crowd, Naveed Abbasi, said he is convinced Sharif was a victim of conspiracy but that, " God willing, the people will make Nawaz Sharif again the prime minister ... for a record fourth time".
Nawaz Sharif told party leaders that Almighty Allah favours what is right and just.
Pakistan Tehreek-i-Insaf (PTI), the ruling party led by former cricketer Khan, said the judiciary was independent and the cases would continue. From there, they were to fly to the eastern city of Lahore.
The Islamabad High Court suspended the 10-year sentence for Mr Sharif and the seven-year term handed down to his daughter, Maryam, over corrupt practices linked to his family's ownership of expensive London flats.
It was not clear when Sharif's appeal will be heard.
The IHC's division bench comprising Justice Athar Minallah and Justice Miangul Hassan Aurangzeb allowed the petitions of the Sharif family members against the accountability court's July 6 judgment in the Avenfield Apartments reference. "It also failed to prove how was Maryam Nawaz sentenced under the same charge sheet which convicted Nawaz Sharif". In April this year, he was barred from running for public office for life, after the SC ruled that he had lied on a parliamentary wealth declaration and that the disqualification from that crime would last for an indefinite period.
An AFP reporter at the scene said Sharif, Maryam and his son-in-law Captain Safdar were driven away in an SUV as it was pelted with rose petals in celebration. The accountability court verdict had ruined their political career.
On July 6, accountability court judge Mohammad Bashir had convicted Nawaz, Maryam and Capt (retd) Safdar in the Avenfield properties reference and sentenced them to 11, eight and one year, respectively.
The applicants have been asked to submit suerty bonds of Rs5 00,000 each before they are released from Adiala Jail. They returned to jail on Monday.
He said Mian Nawaz Sharif was jailed in order to pave the way Imran Khan, the incumbent prime minister. He faces several court cases at home.
The PPP leader criticised the National Accountability Bureau (NAB) for what he termed "incompetence" in pleading the case against the court. The bench also imposed a fine on the NAB lawyers earlier for using delaying tactics.
Both appealed against the sentences and have denied any wrongdoing.