Lockport Township High School (LTHS) is a public high school in Lockport, Illinois, United States.

Lockport is a city in Will County, Illinois, United States, located 30 miles southwest of Chicago. Per the 2020 census, the population was 26,094. The city was incorporated in 1853. It is situated along the Illinois and Michigan (I&M) Canal, and was the headquarters of the canal when the canal was operating. A section of the canal runs through Lockport, including the remains of the canal's Lock No. 1 from which the town received its name. The canal right-of-way is now the Illinois and Michigan National Heritage Corridor.