Tyson is a Lhasa Apso/Chihuahua cross, and he lives in Lincolnshire with Rosemarie McLinden and her family.
Oh, he's also just four inches tall. That's about the size of a standard grapefruit.
In fact, Tyson can stand comfortably on McLinden's outstretched hand – which could make him Britain's littlest dog. "I've been doing a lot of research and I can't see a smaller dog anywhere in the entire country," McLinden told The Express.
Tyson hasn't grown much since birth, when he was rejected by his siblings and was even too small to breastfeed. Instead, he was fed through a pipette by hand.
But, although no collars fit him – and his larger siblings occasionally mistake him for a toy – Tyson is doing well, as you can see from this video.