Blackberry Run is a tributary of East Branch Fishing Creek in Sullivan County, Pennsylvania, in the United States.

The stream is acidic and is considered by the Pennsylvania Department of Environmental Protection to be impaired by atmospheric deposition.

[1] Blackberry Run joins East Branch Fishing Creek 3.08 miles (4.96 km) upstream of its mouth.

[2] It is the last named tributary to join East Branch Fishing Creek before it reaches its mouth.

One proposed method of increasing the alkalinity of the stream is the construction of vertical flow wetlands at its headwaters.

Other proposed methods include road liming and high flow buffer channels.

[3] Blackberry Run is designated by the Pennsylvania Department of Environmental Protection for use by aquatic life.

[1] The lower half of Blackberry Run flows over rock of the Catskill Formation.

[3] Blackberry Run was used as a water supply for industrial and domestic uses, in particular, for the residents of Jamison City, in the early 1900s.

[3] Blackberry Run was listed as impaired by the Pennsylvania Department of Environmental Protection in 2002.