Giovanni Battista di Quadro (, ; died between 10 April 1590 and 16 January 1591) was an Italian Renaissance architect active in Poland.
He was born Ponte Tresa or Cadro, near Lugano (today Switzerland).
Until 1550, he probably worked in Saxony and Silesia, but on 13 March 1550, he signed a contract with the city council of Poznaà  for rebuilding the town hall. In 1551, with the agreement of the council, he went to Pà Âock as a consultant on the renovation of the cathedral. In the same year, his name was mentioned in the court books of Poznaà  because of links between him and the Bishop of Poznaà  Benedykt Izdebski relating to building the bishop's palace in Krobia. From 1552 to 1562, di Quadro was the City Architect of Poznaà Â, but the City Council also paid him in 1563, 1566, 1567, and 1570 for minor works. During these years, he worked for the citizens of Poznaà  and the clergy and nobles of Greater Poland.
From 1568 to 1572, he worked in Warsaw, rebuilding today's Royal Castle.
His many well-paid jobs made him wealthy. However, after he retired in 1573, he died as an indebted person in Poznaà Â.
During the years 1550-1552, his brothers Antoni, Gabriel, and Kilian di Quadro also worked in Poznaà Â.
Works (existing and no longer existing) attributable to him, on analysis of style and unverified documents):