The Avoca Lake, formerly known as Avoca Lagoon and as Bulbararing Lagoon, is an intermittently closed intermediate saline coastal lagoon that is located on the Central Coast of New South Wales, Australia. Avoca Lake is located between the beachside settlements of North Avoca and Avoca Beach, and adjacent to the Pacific Ocean, about 85 kilometres (53 mi) north of Sydney.

The Avoca Lake is fed by stormwater runoff into Saltwater Creek that gathers on the slopes within Kincumber Mountain Reserve to the northwest above Pickets Valley. The lake has a surface area of approximately 70 hectares (170 acres) and a catchment area of 10.8 square kilometres (4.2 sq mi). Its outflow is into Bulbararing Bay in the Tasman Sea of the South Pacific Ocean. The outflow is generally closed, and water levels inside the lake are not usually influenced by ocean tides.

Bareena Island lies entirely within Avoca Lake.

Terrigal Lagoon and Wamberal Lagoon are located to the north and are a short distance away.

• List of lakes of Australia

• "Gosford Lagoons & Sydney Northern Beaches" (map). Office of Environment and Heritage. Government of New South Wales.
• McCormack, Robert B. (September 2010). "Avoca Lagoon Catchment: Freshwater Aquatic Biodiversity Survey" (PDF). Australian Aquatic Biological Pty Ltd. Gosford City Council. Archived from the original (PDF) on 26 June 2014. Retrieved 6 April 2013.
• "Gosford Coastal Lagoons Processes Study: Volume 1: Main Report & Figures" (PDF). Cardno LawsonTreloar. Gosford City Council. July 2010. Archived from the original (PDF) on 26 March 2012. Retrieved 6 April 2013.
• "Gosford Coastal Lagoons Processes Study: Volume 2: Appendices" (PDF). Cardno LawsonTreloar. Gosford City Council. July 2010. Archived from the original (PDF) on 26 March 2012. Retrieved 6 April 2013.