|Location||Argyll and Bute, Scotland|
|Primary outflows||River Avich|
|Max. length||3.3 mi (5.3 km)|
|Max. width||0.5 mi (0.80 km)|
|Surface area||348.2 ha (860 acres)|
|Average depth||98.5 ft (30.0 m)|
|Max. depth||188 ft (57 m)|
|Water volume||3,327,000,000 cu ft (94,200,000 m3)|
|Shore length1||13.5 km (8.4 mi)|
|Surface elevation||93 m (305 ft)|
|1 Shore length is not a well-defined measure.|
Loch of Avich is a large freshwater loch that lies approximately 1 mi (1.6 km) west of Loch Awe in Argyll and Bute in Scotland. It is the second biggest loch in the Etive basin after Loch Awe. It trends east-northeast, west-southwest and is narrowly triangular in shape. At the southwest end of the loch is the islet Innis Luana on which stands the ruins of an ancient castle named Caisteal na Nighinn Ruaidhe (Castle of the Red Haired Maiden). The castle may have been the original seat of Clan Campbell. Near the north shore on the islet of Eilean Fraoch is the remains of a crannog.
The loch was surveyed on 26 and 27 May 1903 by Sir John Murray, T.N. Johnston, R.B. Young, R.C. Marshall and E.M. Wedderburn and later charted  as part of Murray's Bathymetrical Survey of Fresh-Water Lochs of Scotland 1897-1909.
- "Loch Avich". British lakes. British Lakes. Retrieved 4 March 2015.
- Gazetteer of Scotland. Edinburgh, Scotland: Thomas Turnbull and Sons. 1825. p. 23. Retrieved 4 March 2015.
- "Bathymetrical Survey of the Fresh-Water Lochs of Scotland, 1897-1909, Lochs of the Etive Basin". National Library of Scotland. Retrieved 5 March 2015.
- "Caisteal Na Nighinn Ruaidhe, Loch Avich". Canmore. Retrieved 5 March 2015.
- Way, George and Squire, Romily. (1994). Collins Scottish Clan & Family Encyclopedia. (Foreword by The Rt Hon. The Earl of Elgin KT, Convenor, The Standing Council of Scottish Chiefs). pp. 90 - 92.
- "Eilean Fraoch, Loch Avich". Canmore. Retrieved 5 March 2015.
- "Loch Awe (upper section) including Lochs Avich & Ederline (Vol. 6, Plate 122... - Bathymetrical Survey, 1897-1909 - National Library of Scotland". National Library of Scotland. Retrieved 5 March 2015.