Generally associated with deep holes in rivers, the Murray cod prefers habitats with instream cover such as rocks, stumps, fallen trees or undercut banks. A 'sit and wait' predator, its diet contains fish, crayfish and frogs.

It has only recently been discovered that Murray cod make an upstream migration to spawn. This movement can be up to 120 km and generally occurs in late winter/early spring when river levels are high. After spawning the fish move downstream again, returning to the same area they occupied before the migration, usually to exactly the same snag.

The species matures at 4-5 years of age and 500-600 mm total length, and spawns in spring and early summer when water temperatures exceed about 15°C. Eggs are large (3-3.5 mm diameter), adhesive and usually deposited onto a hard surface such as logs, rocks or clay banks. The male guards the eggs during incubation and they hatch after 5-13 days. The larvae are about 5-8 mm long at hatching and have a large yolk sac. Larvae drift downstream for 5-7 days, particularly by night in spring and summer (late-October-mid-January, peaking from mid-November-mid-December).

Murray cod is a long-lived species: average weights for fish from rivers aged 5, 10, 15, 20 and 30 years is approximately 5, 10, 15, 20 and 36 kg respectively. The oldest cod that has been accurately aged was 48 years old, 1280 mm long and weighed 32.5 kg, but younger fish may be larger, e.g. one was 29 years and 34 kg.