In the title compound, C(24)H(39)NO(2)·H(2)O, the A and C rings of the pregnolene derivative sterol adopt chair conformations, with the B ring in a flattened chair conformation and the five-membered ring in an envelope conformation twisted about the C/D ring junction. The N-tert-butyl-carboxamide substituent is equatorial. The 3β-hydr-oxy H atom and one H atom of the water mol-ecule are disordered over two positions with equal occupancies. In the crystal structure, O-H⋯O hydrogen bonds between the 3β-hydr-oxy groups of neighbouring mol-ecules form dimers in the bc plane and these dimers are stacked along the a axis by additional O-H⋯O hydrogen bonds involving the water mol-ecules. The steric effect of the bulky tert-butyl substituent in the carboxamide chain precludes hydrogen-bond formation by the N-H group.