A simple and compact flame atomic absorption spectrometer (FAAS) was constructed to carry outsimultaneous multielement determination of calcium and magnesium in water. In this instrumental system, ahandheld and computer-controlled charge coupled device (CCD) spectrometer was used as the detector, anda calcium and magnesium multielement hollow cathode lamp was used as the light source. The instrumentallimits of detection (LOD) were 0.5mgl-1 and 0.03mgl-1 for calcium and magnesium, respectively. Calciumand magnesium in a water sample were simultaneously determined, with the analytical results in goodagreement with those by inductively coupled plasma optical emission spectrometry (ICP-OES). Therecoveries for calcium and magnesium standards added to the water sample were in the range of 103-114%.