Mr Di Resta, 27 - a driver with the Sahara Force India Formula 1 team who comes from Uphall, West Lothian - told Mrs Justice Asplin he "could not trust" anything Mr Hamilton was going to do.
He was giving evidence at a High Court trial in London after being sued by Mr Hamilton for wrongful termination of a contract.
"I had lost all trust," he said. "I could not trust anything he was going to do and anything he was going to do to represent me."
Earlier, a lawyer representing Mr Hamilton said Mr Di Resta had made a "scandalous" allegation of "fraudulent misrepresentation".
Charles Hollander, QC, asked whether Mr Di Resta had made up the allegation in order to get out of his agreement with Mr Hamilton.
Mr Di Resta replied: "Absolutely not.'
He said Mr Hamilton had been dishonest in an email by saying he was "required" to sign a management deal before getting a Force India driver's slot.
Mr Hollander said: "This was a scandalous allegation of making a fraudulent misrepresentation to you."
Mr Di Resta replied: "I did not choose the words. I told the story to the solicitors. They wrote it."
Mr Di Resta said: "He was dishonest in the information he was giving to me to ensure I signed this contract. I took directions from my solicitors."
The hearing continues.