Luigi Maria Marelli (1858-1936) was an Italian prelate named by pope Benedict XV bishop of Bergamo.

[1] Born in Milan, Marelli was appointed bishop of Bobbio by pope Pius X in 1907 and in 1914 after the death of Giacomo Radini-Tedeschi he was transferred to the see of Bergamo.

In 1920 pope Benedict XV sent to Marelli a letter, in the letter the pope affirmed the duty of the church to fight against Socialism but he also reaffirmed the importance of social teaching of Catholic Church[2] Marelli died in 1936 in Rho, Lombardy.