A bolometric detector including an absorbing part intended to convert incident electromagnetic radiation into calories, an active part (2) including a sensitive area made of a bolometric material the resistivity of which varies, in a known manner, with temperature, and electrodes that are in contact with the bolometric material (6) over at least part of their surface area. Support areas or posts (3) intended to maintain the active part (2) are suspended above a substrate (1) that accommodates, in particular, the read-out circuit associated with said detector and to ensure electrical conduction between the read-out circuit and the active part, the support areas or posts (3) have regions of non-uniform cross-sectional area between their point of contact with the substrate and the area where they are joined to the active part or being associated with elements that have such non uniformities.