Filter element

A filter element (1) has an inner body (12) and an outer body (11). One casing body (12) has a cross section deviating from circularity. Body contact surfaces (20, 21) face one another for the contact of essentially all filter folds (18a-18f, 18I-18III) of a pleated filter web (10). The filter folds (18a-18f, 18I-18III), in terms of fold height (h), are divided into individual groups (I, II) each having several filter folds (18I-18II) of a common fold height (hmax, hmin) alongside one another in sections. Between two adjacent filter folds (18a-18f, 18I-18III) of different groups (I, II) filter folds are arranged (18b-18e; 18m) of at least one third group (III). The filter folds (18b-18e, 18m) of the third group (III), in the manner of step formation, have a common fold height (hD) different from the respective fold height (hmax, hmin) of the filter folds (18I-18II) of the two adjacent neighboring groups (I, II), and/or, in the manner of curve formation, have different fold heights, establishing a transition between the fold heights (hmax, hmin) of the two adjacent groups (I, II).