Triadobatrachus was 10 cm (3.9 in) long, and still retained many primitive characteristics, such as possessing at least 26 vertebrae, where modern frogs have only four to nine.

Its skull resembled that of modern frogs, consisting of a latticework of thin bones separated by large openings.

[2] This creature, or a relative, evolved eventually into modern frogs, the earliest example of which is Prosalirus, millions of years later in the Early Jurassic.

[1][6] Although it was found in marine deposits, the general structure of Triadobatrachus shows that it probably lived for part of the time on land and breathed air.

[8] Triadobatrachus is similar in age to the salientian Czatkobatrachus which is known from the Early Triassic (Olenekian) of Czatkowice [pl] Poland.