Abstract: A coffee percolator having a brewing chamber wherein at least one of the boundary wall surfaces of the brewing chambr is adjustable transversely of the direction of flow of the hot water through the coffee powder so that the thickness of the coffee powder bed in the direction of flow may be kept substantially constant for the coffee charges of varying size. The coffee percolator may include a brewing sieve having a support sieve with openings of a size exceeding the dimensions of the ground coffee particles and a fine sieve supported on the side of said support sieve facing towards the brewing chamber and having openings of a size smaller than the dimensions of the ground coffee particles.