Tibet is part of China politically, so to travel into Tibet, a valid Chinese visa is a must-have document for sure. Tibet is the only province in China that requires a travel permit and a pre-organized tour for non-Chinese tourists.
There is no “permit-only” service for Tibet tours; the permit is part of an organized tour. To get the permit, you have to send by email the scan (or photo) copy of your passport and Chinese visa to your Tibet tour operator who will help to get it at Tibet Tourism Bureau; however, when you go to a Chinese Embassy or Consulate General to apply for a Chinese visa, if the officers there know you plan to travel into Tibet while in China, they will ask you to present them the Tibet permit firstly. It’s obviously impossible to present them the permit before getting the visa, because Tibet permit is only issued by the Tibet Tourism Bureau after passport and Chinese visa copies presented. The rules are contradictory apparently, which just indicates that the Chinese government does not expect (too many) foreign tourists to visit Tibet due to the political sensitiveness there.
On the other hand, there are hundreds of thousand non-Chinese tourists visit Tibet each year if Tibet is not closed for political reasons, how do those tourists get their Chinese visa? The answer is the visa applicants did not mention Tibet tour plan in their Chinese visa application form, instead, the applicants just wrote their tours in China proper only, such as a tour in Beijing, Xi’an Shanghai or Chengdu. Rest assured that you will have no problem for doing this “white-lie”; the Chinese embassies will not track where you visit in China. You can visit whatever places you like after you obtaining your Chinese visa as long as laws in China is followed by you.
The Chinese visa application form(Download) and rules are the universally the same at different Chinese Embassies in different countries. In order to get Chinese tourist (L category) visa, you have to finish the following paper works at your local Chinese Embassy or Consulate；
Original passport with at least six months of remaining validity and blank visa pages; plus a photocopy of the passport's data page and the photo page if it is separate
(2) Visa Application Form and Photo
One completed Visa Application Form with a recently-taken color passport photo (bare-head, full face) against a light background attached
(3) Proof of legal stay or residence status (applicable to those not applying for the visa in their country of citizenship)
If you are not applying for the visa in the country of your citizenship, you must provide the original and photocopy of your valid certificates or visa of stay, residence, employment or student status, or other valid certificates of legal staying provided by the relevant authorities of the country where you are currently staying.
(A): Documents showing the itinerary including air ticket booking record (round trip) and proof of a hotel reservation.
(B): If documents mentioned in item A cannot be present, you should present an invitation letter issued by a relevant entity or individual in China. The invitation letter should contain:
(1) Information on the applicant (full name, gender, date of birth, etc.)
(2) Information on the planned visit (arrival and departure dates, place(s) to be visited, etc.)
(3) Information on the inviting entity or individual (name, contact telephone number, address, official stamp, signature of the legal representative or the inviting individual)