The Long Cove Creek railway viaducts are heritage-listed railway viaducts which carry the Main Suburban railway line over Long Cove Creek between the suburbs of Lewisham and Summer Hill in Sydney, New South Wales, Australia. The viaducts were designed and built by the New South Wales Government Railways. The property is owned by RailCorp, an agency of the Government of New South Wales. It was added to the New South Wales State Heritage Register on 2 April 1999.