She said the Chancellor was out of his depth and a "pernicious influence" on the economy and David Cameron.
Ms Dorries said in a web interview there was a "personal element" to some of her criticisms after the Prime Minister jibed that she was "extremely frustrated" in the Commons last year.
She said her animosity to Mr Osborne stemmed from his role in defeating a parliamentary amendment designed to restrict abortion counselling.
She said: "He might be a politician and a strategist and a political campaigner. I don't think he's up to the job of being Chancellor."