<jats:title>Abstract</jats:title><jats:p>A new 4‐sulfated ceramide, ircisulfamide (=<jats:italic>N</jats:italic>‐[(1<jats:italic>S</jats:italic>*,2<jats:italic>S</jats:italic>*,3<jats:italic>R</jats:italic>*)‐2‐hydroxy‐1‐(hydroxymethyl)‐3‐(sulfooxy)heptadecyl]hexadecanamide; <jats:bold>1</jats:bold>), and a new glycosphingolipid, ircicerebroside (=(2<jats:italic>R</jats:italic>*)‐<jats:italic>N</jats:italic>‐{(1<jats:italic>S</jats:italic>*,2<jats:italic>R</jats:italic>*,3<jats:italic>E</jats:italic>,7<jats:italic>E</jats:italic>)‐1‐[(<jats:italic>β</jats:italic>‐<jats:sc>D</jats:sc>‐glucopyranosyloxy)methyl]‐2‐hydroxy‐8‐methylheptadeca‐3,7‐dienyl}‐2‐hydroxyeicosanamide; <jats:bold>2</jats:bold>), were isolated from the aqueous EtOH extract of the marine sponge <jats:italic>Ircinia fasciculata</jats:italic> (P<jats:sc>allas</jats:sc>). The structures of the new compounds were elucidated on the basis of spectroscopic analysis and by means of chemical methods.