The new coin - which will feature a mischievous Tom Kitten - will go on sale in August, and will follow in the footsteps of Jemima Puddleduck, Squirrel Nutkin and Mrs Tiggywinkle in 2016, and Peter Rabbit and Jeremy Fisher earlier this year.
The coins are part of the Royal Mint's celebratory collection in honour of Beatrix Potter - the literary genius behind children's classics The Tale of Peter Rabbit and The Tale Squirrel Nutkin.
Tom Kitten - which is expected in just a matter of weeks - will be available to buy in both colour and silver at the Royal Mint's online store.
It leaves one final edition - Benjamin Bunny - which is expected out in the autumn.Royal Mint launches stunning new Peter Rabbit 50p coins - but you'll have to queue for FOUR hours to get your hands on one
Where can I buy one and when?
The coins have been printed in colour, making them a collectors' dream
Collectors hoping to get their hands on one of the precious new coins will have to head to Royalmint.com on the day of release - the coins are due out in August although a final date is yet to be announced.
The coins won't enter circulation, so to get one, you'll have to pay - they usually come in at around £60 each.
The stunning Peter Rabbit edition that launched earlier this year
Speaking at the time of the Peter Rabbit release, Anne Jessopp, of The Royal Mint, said: "While we always knew that the Beatrix Potter characters would be a huge hit, the enormous popularity of the 2016 set exceeded everyone's expectations.
"The coins sold out almost instantly as people raced to collect a complete set of the four friends. We're delighted to be able to present another group of her exquisite characters, giving them a new lease of life on our specially-designed coloured commemorative coins."
What does the Tom Kitten coin look like?
It'll feature replica illustrations from the children's books
The Tom Kitten coin will feature a stunning illustration of the wide-eyed cat and will be available to buy in both standard silver and in colour.
The design was deliberately chosen to reflect the hand-painted illustrations as featured in Beatrix Potter's iconic children's books, which date as far back as 1902.
The reverse side will show the definitive Jody Clark portrait of the Queen - which can be found on many 50p coins currently in circulation.
The story behind the new 50p designs
45 million copies of The Tale Of Peter Rabbit have been sold since 1902
Royal Mint coin designer Emma Noble was chosen to immortalise Potter's much-loved illustrations in this year's collection.
The designer has previously worked on coins commemorating the 60th anniversary of The Queen's coronation, Remembrance Sunday, and King George I.
Brand manager for Peter Rabbit at Penguin Ventures Thomas Merrington said: "We are so delighted to be working once again with The Royal Mint on a new series of Beatrix Potter coins.
Jeremy Fisher is another in the stunning collection
"The success of the original range is testament to the incredible craftsmanship and attention to detail that Emma Noble achieved in her designs and also to the love and affection shown towards Beatrix Potter's characters by the general public."
"We can't wait to see which of the new character designs will be most popular."