Introducing a so-called "tourist tax" is to be debated by the London Assembly.
More than 40 million overnight visitors are expected to visit the capital a year by 2025 - a rise of 30% on the 2016 numbers.
Supporters believe between £91 million and £364 million could be raised from a small tourism charge levied on accommodation.
This money could then be used to support culture and tourism.
The scheme, which is already in place across major cities such as New York, Berlin and Paris, is to be discussed on Tuesday at City Hall.