The 35-year-old has been hit by injuries in recent years and his Euro 2016 campaign was cut short by a thigh injury.
He saw limited action last season and made just 170 Premier League appearances for Arsene Wenger's men after joining Arsenal from Borussia Dortmund in 2006.
Rosicky made his professional debut in 1999 for Sparta before joining Borussia Dortmund in 2001.
Media reported Sparta will introduce Rosicky at a news conference later on Tuesday.
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(Reporting by Jason Hovet; editing by Amlan Chakraborty)
