Nadine Dorries is to be investigated by the parliamentary standards commissioner over payments for her appearance on I'm a Celebrity Get Me Out Of Here.
Money has been paid to a company of which she is director, but she insists she has not taken any payment, the BBC has reported.
She has told Ross Hawkins, the BBC's political correspondant, that her personal finances are "her own business and nobody else's. "
She added "I'm a backbencher not a minister. If I choose to take money from the company then I will declare it immediately"
She posted on Twitter she felt "hounded" by the accusations, writing: "LABOUR MP John Mann reported me to Standards Commissioner for undeclared earnings. Anything I earn, I declare IMMEDIATELY.
"If I haven't declared anything, it's because I haven't earnt anything. I must be the most hounded MP in Parliament."
Earlier this year she told the BBC's Sunday Politics programme she had not "personally" benefited from appearing on the show.
Dorries was the first person voted off the show
Her participation on the jungle reality show caused a stir in Westminister and the MP had her whip suspended due to her absence from parliament.
Although Ms Dorries said she was in the jungle as it was "a golden opportunity to communicate with sixteen million people", the Mid-Bedfordshire MP's ambitious principles were questioned after she was filmed chewing on a lamb's testicle and ostrich's anus in the notorious Bushtucker Trials.
Her whip was restored in May.
Dorries has a chequered history with the Independent Parliamentary Standards Authority (Ipsa). She launched a stinging attack on the commision earlier this year after it announced it was investigating whether she had abused her expenses over a separate concern.
She claimed that the behaviour of Ipsa was putting off women from becoming MPs and she would fight the allegations in the interests of women's rights. She said the authority would rather have her put down her dog than claim expenses and suggesting Ipsa had targeted her due to her fame.
"I am quite sure the Ipsa solution to my being a single mum and lone carer of a family and a dog would be to have the dog put down and my child adopted, but I’d rather not," she said at the time.