Tube-dwelling anemones, animals belonging to the subclass Ceriantharia, are characterized as essential organisms for reef structures, playing complex ecological relationships with other living beings. However, the difficulty in collecting specimens leads to a lack of detailed environmental and biogeographical studies for the subclass, given the challenges in implementing laboratory cultures. Ecological Niche Modelling (ENM) is an important tool for biodiversity distribution studies as it allows for mapping the environmental aspects related to this distribution. It is useful in studies of species with gaps in ecological and biogeographical knowledge, helping to understand the potential and realized niche aspects. Thus, the present study aimed to analyze the realized niche of nine species of Ceriantharia in the Atlantic Ocean through Ecological Niche Modelling (ENM), implemented with the MaxEnt algorithm, to enrich knowledge about new zones of environmental suitability for ceriantharians and, consequently, identify potential new occurrence sites. All models were statistically significant (AUC ≥ 0.7; TSS ≥ 0.4) and aligned with the known biology of the animals, with only a few extrapolations in areas inaccessible to tube anemones. This study aimed to consolidate current knowledge on the ecological niche of ceriantharians in the Atlantic Ocean, assisting in identifying priority areas for marine biodiversity conservation. Based on the results, a highlighted need exists to intensify data collection efforts on these organisms and review database records to minimize potential identification errors.