Britain's Dragon's Den was based on the Japanese television series Money Tigers.
Money Tigers supplied the core format: entrepreneurs present proposals to wealthy investors and attempt to negotiate funding in exchange for equity. The concept was adapted for different countries, with each version changing the investors, language, business examples and branding while retaining the pitch-room structure.
The British programme uses “Dragons” as its name for the investors, which is why its title differs from the Japanese original. The American adaptation is known as Shark Tank, another example of the same international format receiving a local identity.
The title is sometimes confused with the literal Japanese name, Money no Tora, or with later English-language programme titles. “Money Tigers” is the English title generally cited for the Japanese original in accounts of the format's history, making it the precise answer to this question.