Do I need an invitation letter to apply for a British tourist visa?

No, when you apply for a British visa, you only need to provide invitations for travel and business. If you are traveling, you can prepare the UK visa materials normally, and you don't need to provide an invitation letter.

However, when applying for a British visa, it is still necessary to meet higher requirements, because the British Embassy in China is very strict with applicants, and only when there is no problem with the materials can you get a visa smoothly. /zd/ym