Mahmoud Abbas, 82, was admitted to a hospital in Ramallah early on Sunday.
He is expected to stay at least until later today.
The leader of the Palestine Liberation Organisation underwent surgery on his ear last Tuesday, 15 May.
The medical director of the private al-Istishari hospital where the President is staying said the patient was undergoing “medical tests”.
Dr Saed al-Sarahneh told cameras outside of the hospital on Sunday evening the president had been admitted earlier in the day “for medical tests for the surgery he had three days ago in his middle ear.
He added: “All the tests are normal and his medical condition is reassuring.”
One Palestinian official reaffirmed the admission was as a result of Tuesday’s procedure.
He said the politician had been found with a temperature “so doctors advised that he go back to hospital”.
The President’s party were keen to reassure the public of their leader’s health.
They posted on their official Twitter account “the president is in good health”.
The country’s chief negotiator, Saeb Erekat visited him in hospital on Sunday. An aide said the politician had talked and joked with him.
But, an anonymous source at the hospital said the treatment was for an unrelated chest condition.
The source, who spoke on the condition of anonymity, told Reuters:
“He is being given antibiotics to treat an inflammation in the chest.
“The president will stay in hospital until tomorrow.”
The president is known to be a heavy smoker.
The illness has coincided with an escalation in Palestinian-Israeli tensions.
Israeli troops shot dead around 60 Palestinians on the Gaza border last Monday, May 14, as the new American Embassy opened in Jerusalem.
Trump’s decision to move the national office broke decades of American protocol of not opening embassies on disputed land until a peace deal is reached.