Most likely, yes.
Many, though not all, travelers heading to Vietnam will require a visa.
Citizens of several European states, for example, can travel as tourists to Vietnam without a visa if their stay is under 15 days; and citizens of several southeast Asian nations can enter and remain in Vietnam without a visa for stays of up to 30 days. But travelers from the United States, Canada, and Australia, among many other countries, require a visa to enter Vietnam regardless of the length of stay or the purpose of the trip.
Tourists who require a visa to enter Vietnam can apply online in advance and obtain their paperwork upon arrival in one of the country’s four international airports (Hanoi, Da Nang, Ho Chi Minh City, Nha Trang). After filling out the application and paying the service fee online, travelers will receive an official visa approval letter from Vietnam’s Immigration Department via e-mail within two business days. Once you’ve been approved, print out the letter and bring it — along with two passport photos — with you on the plane to present in Vietnam upon landing. A stamping fee will be charged when you obtain your visa.
Tourist visa fees, when applying online, vary according to processing speed (as slow as two working days and as fast as four hours), duration of visit (one to three months), and a single-entry versus multiple-entry visa: they can run as little as $17 or as much as $65. Travelers can also pay for services in addition to their visa online, such as access to an airport processing fast-lane ($25) or car transport service to your hotel ($30). Stamping fees also vary depending on whether a visa is for single or multiple-entry, costing $25 for the former and $50 for the latter. Travelers must pay for the stamping fee in cash, using either Vietnam dong or U.S. dollars.
Travelers also have the option of visiting an official embassy as early as six months prior to your departure, and submitting the necessary materials in person. If you're located near an embassy or consulate (New York City or Washington, D.C. for example) you may find this preferable, as it will expedite your entry into Vietnam after landing.