Santissimo Sudario all'Argentina ([Church of] the Most Holy Shroud at the Argentina) or Santissimo Sudario dei Piemontesi (Church of the Most Holy Shroud of the Piedmontese) is a church in Rome, sited on the via del Sudario in the Sant'Eustachio district.

Originally dedicated to Saint Louis of France, it was rebuilt in 1605 by the Archconfraternity of the Savoyards and Piedmontese, which had been founded in Rome at the end of 1537 under the title of the 'sacra Sindone' or holy shroud and promoted to be an archconfraternity in 1592 by Pope Clement VIII.

In 1856 it was restored and in 1870 became a kind of private chapel for the House of Savoy.

A guide from the 19th century ascribes the main altarpiece to Antonio Gherardi, which accompanied a replica of the Holy Shroud.

Other altarpieces depict St Frances of Sales by Carlo Cesi, and a Blessed Amadeo of Savoy by Giovanni Domenico Cerrini; and others by Lazzaro Baldi.