To provide a liquid chemical processing method and a liquid chemical processor for accurately comprehending the progress conditions of etching.

An etching processing end point detection means 40 positions a fiber part 43c, at a measuring position on the surface of a substrate W by an attaching/detaching mechanism 40. A control part 50 performs a first film thickness measuring process T20 in a time lag period T20, during which etching processing is started and performs second film thickness measuring process T21 to fifth film thickness measuring process T24 in the time lag periods T6 to T12, during which the supply of hydrofluoric acid L2 is stopped. That is, the supply of the hydrofluoric acid L2 is stopped intermittently during the etching processing, the film thickness measuring process is performed and the end point of etching is detected.