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Burrowing crabs are considered to be ecosystem engineers, playing a vital role in mangrove ecosystems through bio-geochemical transformation. This process depends on the size and shape of burrows. The present study analyzes the architecture of burrows constructed by crabs in a restored mangrove habitat. Fourteen crab species were found to construct burrows of 13 different shapes, with a predominance of I-, J-, and L-shapes. Sesarmids were larger in size than fiddlers, and made burrows with wider openings mostly in the <i>Rhizophora</i> zone. Fiddlers constructed complex burrows with a vertical position, and made longer and deeper burrows in contrast to sesarmids, which formed simple burrows with a horizontal position, digging shorter and shallower burrows in <i>Avicennia</i> or open zones. The sesarmids had smaller burrows without branching in mangrove zones, whereas the fiddlers had larger burrows with or without branching in open and <i>Avicennia</i> zones. The burrows of fiddler crabs, especially <i>Austruca occidentalis</i> and <i>A. annulipes</i>, had separate openings and passages for exit and entry as an adaptation against predators. The present work identified <i>Austruca occidentalis</i> and <i>A. annulipes</i> as the most potent bioturbating crab species in restored mangrove habitats due to their efficiency in soil excavation and formation of large-sized burrows.