The new range will include shampoo, toothpaste, toothbrushes, wipes, handwash, bubble bath, plasters and shower gel, but rsps have not yet been confirmed.
The products are based on the Horrid Henry series of books created by author Francesca Simon, and the character has become a major international brand.
"We are delighted to have brought Sert-MST on board what is a rapidly expanding programme," said John Taylor, partnerships manager at CPLG, the licensing agent. "Horrid Henry is absolutely huge at present and its popularity is set to go through the roof with the release of the movie this summer."
Last month, Sert-MST predicted turnover growth of £85m over the next 18 months as it moves into licensed goods. It has recently secured a number of licences including Bob The Builder, Transformers, Noddy and Care Bears. It is also in advanced discussions for the Britain's Next Top Model licence.
Sert-MST will have a new brand sales manager from 6 April. Isobel Brunt joins from Betterware UK where she was a buyer and category manager.