Mario Varglien (Italian pronunciation: [ˈmaːrjo ˈvarʎen]; 26 December 1905 – 11 August 1978), also known as Varglien I, was an Italian football player and manager born in Fiume (today Rijeka), who played as a midfielder.

Varglien played club football with Juventus for most of his career, winning five Serie A championships, and also serving as the team's captain.

At international level, Varglien was also part of the Italy national football team which won the 1934 FIFA World Cup.

Mario's brother, Giovanni Varglien also played football in Italy and with the Italy national team; the two brothers played together at Juventus.

This biographical article related to association football in Italy, about a midfielder born from 1900 to 1909, is a stub.