However, the MP for North Shropshire has hit back at what he called a "biased process".
An investigation by the Parliamentary Commissioner for Standards Kathryn Stone found he repeatedly lobbied ministers and officials on behalf of two companies for which he was acting as a paid consultant - Randox, and Lynn's Country Foods.
The Commons Standards Committee said his actions were an "egregious" breach of the rules on paid advocacy by MPs and recommended that he should be suspended for 30 sitting days.
But in an angry statement, Mr Paterson rejected the commissioner's findings, accusing her of making up her mind before she had even spoken to him.
He said: "This is a biased process and not fair.
"It offends against the basic standard of procedural fairness that no-one should be found guilty until they have had a chance to be heard and to present their evidence including their witnesses."
The Committee on Standards acknowledged there were mitigating factors around the investigation into Mr Paterson, including the death of his wife Rose in June 2020.
The report said: "Mr Paterson's wife took her own life in June 2020.
"The committee consider it very possible that grief and distress caused by this event has affected the way in which Mr Paterson approached the commissioner's investigation thereafter."
Relating to the breach of use of his office, the committee also acknowledged Mr Paterson had been suffering from ill health which "made him less able easily to leave the parliamentary estate".
The committee added Mr Paterson's "passion and expertise" in food and farming matters was "admirable, as long as it is channelled within the rules of the House".
Mr Patersonm, 65, is a prominent Brexiteer and a member of the European Research Group (ERG).
His wife Rose died on June 24 of last year.
Her body was discovered in the early hours in woodland at her countryside farmhouse.
A coroner subsequently ruled that she had committed suicide.
(More to follow)