Shares of the biggest U.S. bank by assets rose as much as 2.7 percent to a 14-year high of $63.06 in late morning trading.
JPMorgan said in July that Dimon, 58, had been diagnosed with throat cancer, but the ailment was curable.
Dimon said on Friday his treatment ended a few months ago, although his health would be monitored for several years.
He said he was following the advice he gives others - "take care of your health first."
JPMorgan's shares were up 2.4 percent at $62.85 on the New York Stock Exchange.
(Reporting by Tanya Agrawal in Bengaluru; Editing by Kirti Pandey)