Vipera seoanei is a venomous viper species endemic to extreme southwestern France and the northern regions of Spain and Portugal.

[3] This is a highly polymorphic species for which four main color-pattern types have been described:[3] A: well-developed, brown zigzig pattern down the back, very much like V. berus, set against a beige or light-gray ground color.B: roughly twin-striped pattern, with the ground color expressed as two narrow, straight, dorsolateral longitudinal lines along the body.

Resembles V. kaznakovi to some degree.C: uniform brownish morph with no pattern.D: fragmented zigzag pattern (see V. s. cantabrica).Vipera seoanei is found in extreme southwestern France and the northern regions of Spain and Portugal.

The type locality is given as "In montibus Gallaecorum et Cantabrorum...d'Espagne" (the mountains of Galicia and Cantabrici, Spain).

[9] It was given this status due to its relatively wide distribution, presumed large population, and because it is unlikely to be declining fast enough to qualify for listing in a more threatened category.