Communications director Erika Coghlan is to quit the NFU after just six months in the role.
The former Coca-Cola vice-president, who joined the NFU in January, will formally leave her post on Friday (10 June).
NFU policy director Martin Haworth said Ms Coghlan had decided she no longer had enough time to devote to the union alongside her equine business.
Mr Haworth said: “We would like to thank Erika for her contribution in developing the communications function and wish her well in the future.”
Ms Coghlan becomes the third person in 18 months to leave the NFU after looking after the union’s communications strategy.
The revolving door started spinning when NFU communications director Liz Falkingham quit last spring, citing personal reasons.
She was succeeded by NFU head of government affairs Terry Jones, who was appointed acting communications director.
He left following Ms Coghlan’s appointment and is now director of communications at the Food and Drink Federation.
The NFU must now search for its fourth communications director in the four years since Anthony Gibson left at the end of 2007.
Born in rural Derbyshire, Ms Coghlan gained an economics degree before embarking on a career in the drinks industry.
She was recruited from Coca-Cola, where she was vice-president of corporate affairs for Coca-Cola Enterprises in the UK.
Her CV includes roles heading up communications at the Food Standards Agency and working for the European Commission and Defra.
Ms Coghlan lives on a sports horse stud in south Warwickshire. In her spare time, she rides and judges dressage.