Idress Kamal, the head of an anti-militancy civil society group that has taken up Afridi's case, said an appeal had been filed in a court in Peshawar against the doctor's conviction.
The appeal also challenges the sentence and charges levelled against Afridi, he said.
Afridi was arrested days after bin Laden was killed in a unilateral American raid in the garrison town of Abbottabad on May 2 last year.
Though he was accused of assisting the CIA track bin Laden through a fake vaccination campaign, he was convicted of helping and funding the banned Lashkar-e-Islam militant group by a tribal court on May 24.
Kamal said the appeal was filed in a court in Peshawar that hears appeals against judgements given by tribal courts under the British-era Frontier Crimes Regulation. "All the charges labelled against him were baseless. Shakeel Afridi had no links with Lashkar-e-Islam," he said.
Significantly, the Lashkar-e-Islam, which is led by commander Mangal Bagh Afridi, has denied any links with the doctor.
A spokesman for the banned group even threatened to kill Afridi.
Afridi's conviction and sentencing has angered the United States, which has called for his release.