Parmesan cheese is a typical substitute for Pecorino Romano cheese. In fact, Pecorino and Parmesan cheeses are commonly used interchangeably, with one easily replacing the other.
Both cheeses are hard cheeses of Italian origin that have a similar texture when grated. They both have a similar salty taste, with the most notable difference being the slightly sharper flavor of Pecorino over Parmesan. The primary difference between the two cheeses is the type of milk used to make them. Parmesan cheese is made from cow's milk, whereas Pecorino cheese is made from sheep's milk. Both pair well with pasta and are popular ingredients in pasta dishes.