Strictly speaking, Lebanon does not have a student visa system: it has a system of limited-duration entry visas
(of from one to six months), and offers residence permit
options to those who have entered the country legally and can provide proof that they are legitimately employed or studying in the country. The OIP staff do not maintain a list of requirements for entry to Lebanon, as governments across the world can and do alter visa regulations and procedures without notifying educational institutions.
The Lebanese consulate or embassy in your home country or country of citizenship is generally the best place to obtain up-to-date information on entry requirements. There is currently a succint and relatively nuanced explanation of entry visa options for Lebanon at this site.
Whenever possible, we recommend that a student who will be here for one semester should try to obtain a 6-month multiple-entry tourist visa prior to coming to Lebanon; we have been informed however, that not all consulates will agree to issue the 6-month tourist visa. If you find that to be the case, you may choose to get a 3-month visa or, if your nationality permits it, you may obtain the one-month single entry visa at the airport, as you enter the country.
If you are planning to study here for more than a semester it is usually prefereable and easier, if your nationality makes it possible, to enter on a tourist visa obtained at the airport(which usually is issued for one month and is a single-entry visa), and obtain the residence permit after you have enrolled at AUB.
To learn more about the airport-issued tourist visa, please see the second paragraph below.
Obtaining the 6-month visa
In order to obtain the 6-month visa, you will need your letter of admission from AUB, and typically you will also need a Certificate for Visa Purposes, which is issued by the AUB Admissions Office. If you have received electronic notification of acceptance to AUB from the Admissions Office, this constitutes your letter of Admission. If you have decided to apply for the 6-month visa, you should e-mail email@example.com , with a subject line header that states: Certificate for Visa Purposes Needed, requesting the certificate and stating whether you wish to receive it via e-mail attachment or fax.
Other visa options
In the event that that you receive your offer of admission too late to obtain a 6-month visa, it is possible for citizens of many countries to enter Lebanon on a one-month tourist visa (obtainable at the airport or border). If you do so, however, you are required to begin the process of obtaining a student residence permit BEFORE the expiration of that month. The OIP will provide you with up to date information on how to obtain a residence permit during international student orientation.
Visas and travel for summer students
There is a cogent explanation of the visa requirements for Summer Arabic Institute students on the CAMES website.