Mrs Hancox, a West Otago sheep and beef farmer, ousted incumbent director Herstall Ulrich in the director election.
Chairman Rob Hewett, from the Manuka Gorge, topped the poll with 41,437,912 votes, followed by Mrs Hancox with 25,241,163 and Mr Ulrich with 20,695,485.
Mr Ulrich, a South Canterbury farmer and former Meat Industry Action Group member, was elected to the board in 2008.
Yesterday, Mrs Hancox said she was ''humbled'' by the support of shareholders and she was determined to work hard for them.
''I'm just so motivated and determined to make a difference,'' she said.
She and her husband Nelson operate Kowai Downs, Mt Allen and Wohelo Ltd, a sheep and beef finishing operation with 27,000 stock units. They have four children.
The couple have received various farming accolades including Rabobank Lincoln University Foundation South Island Farmer of the Year, Clutha District Farmer of the Year and winners of the national ewe hogget competition.
Mrs Hancox was a founding member of Meat Industry Excellence (MIE), which is seeking industry reform, and resigned from the group to pursue election.
She admitted she was nervous before the results were announced, as she was not sure ''which way it would go'', but farmers had spoken, she said.
A lot of farmers were frustrated and hurting and there would be a lot that would not be paying tax this year, she said.
Asked what she wanted to achieve, Mrs Hancox said collaboration was going to be key.
She wanted a return to sustainable profitability for Silver Fern Farms and improved returns for shareholders.
In 2013, former MIE executive members Richard Young and Dan Jex-Blake were elected to the Silver Fern Farms board.
They were ''like-minded'' directors who saw that scale and collaboration were ''really important, going forward'', she said.
While very excited about her appointment, Mrs Hancox acknowledged it was also a ''huge challenge''.
She will attend her first board meeting tomorrow, which is the same day as the company's annual meeting in Dunedin.
She was the first female farmer representative director on the company's board.
While she was ''rapt'' about that, she had not wanted to play that card, saying she was there, hopefully, because of merit.
• Silver Fern Farms annual meeting will be held at the company's head office, in Princes St, at 11.30am tomorrow.
