No, you cannot enter Laos unless you have an arrival card. Before passing through immigration, all travelers arriving in Laos, regardless of visa type or entry location, must fill out an arrival card.

Arrival cards are often referred to as arriving passenger cards, landing cards, or disembarkation cards.

To enter a nation, some countries require every traveler to have an arrival card. An arrival card is a legal document that must be shown to immigration officials upon arrival. Other nations may just require one card per family unit, while others may only require an arrival card for non-citizen
The card is a document that travelers must fill out and is used by immigration officials to collect information about an arriving passenger that the passenger’s passport does not offer. This information might include your health, criminal past, and the reason for your visit. In certain countries, arrival cards are needed in addition to customs declarations, which incoming travelers must submit individually.

Besides, you need to apply for a tourist visa before departing for Laos. The Laos eVisa is a quick and easy way for visitors to enter the country of Laos. This eVisa is a single-entry visa that permits the tourist to stay in the nation for up to 30 days.