Maryland and Delaware Railroad

The Maryland and Delaware Railroad Company (reporting mark MDDE) is a Class III short-line railroad, formed in 1977 to operate several branch lines of the former Penn Central Railroad in both Maryland and Delaware, United States. These branches were omitted from the system plan for Conrail in 1976 and would have been discontinued without state subsidies. As an alternative to the higher cost of subsidizing Conrail as the operator of the branch lines, the Maryland and Delaware governments selected the Maryland and Delaware Railroad Company (MDDE) to serve as the designated operator. In 2025, it was purchased by Carload Express and folded into that company's Delmarva Central Railroad operation.

The railroad did not own any of the track it uses until 2000 when it acquired a line between Frankford, Delaware and Snow Hill, Maryland from the Snow Hill Shippers Association. The railroad operated on 92 miles of track and ran out of a restored station in Federalsburg, Maryland until 2025 when it was purchased by Carload Express. Concurrent with its sale, the Snow Hill Line was broken into two parts and sold to the Delaware Central Railroad (DCR) and to Old Line Holdings, the company that previously owned the MDDE. After the sale the MDDE operated on just 73.76 miles of track.

The railroad is not affiliated with the similarly named 19th Century Maryland and Delaware Rail Road Company, though it did for a time run on the corridor that the earlier railroad built.