Wallenius is a surname. Notable people with the surname include:
Allan Wallenius (1890–1942), Swedish leftist figure and journalist Asser Wallenius (1902–1971), Finnish Olympian Bror-Erik Wallenius (born 1943), Finnish sports commentator
Johan Fredrik Wallenius (1765–1836), Finnish botanist and physician
Kurt Martti Wallenius (1893–1984), Finnish Major General
Olof Wallenius (1902–1970), Swedish entrepreneur Ville Wallenius, Finnish guitarist who plays in the power metal band Twilightning
See also Wallenius' noncentral hypergeometric distribution, generalization of the hypergeometric distribution where items are sampled with bias Wallenius Lines, privately owned Swedish shipping company included in the Soya Group Wallenius Wilhelmsen Logistics, privately owned Norwegian/Swedish shipping company Zionts–Wallenius method, used to find a best solution to a multi-criteria optimization problem