The general rule regarding foreign visitors to Qatar is that all visitors require a visa, excluding transit passengers (who do not leave the airport) and the citizens of GCC countries (UAE, Kuwait, Saudi Arabia, Bahrain and Oman).
Citizens of the countries listed below can obtain visas on arrival at the port of entrance, in exchange of a fee of QAR 100:
Andorra, Australia, Austria, Belgium, Brunei, Canada, Denmark, Finland, France, Germany, Greece, Hong Kong, Iceland, Ireland, Italy, Japan, Liechtenstein, Luxembourg, Malaysia, Monaco, New Zealand, Norway, Portugal, San Marino, Spain, Sweden, Singapore, South Korea, Switzerland, The Netherlands, USA, UK, Vatican City.