Paints mostly consist of three major components which are binder, pigment/filler andsolvent. Many other components are added in smaller amount and these are calledadditives. One of these additives is defoamers which are added to the paint todecrease foam which can cause defects in the dried paint for example as pores. Thisstudy was about investigating if the defoamers can be identified and quantified withhigh performance liquid chromatography coupled to mass spectrometry. This includessample preparation, chromatographic separation and detector settings. Calibrationcurves where constructed for paints containing different concentrations of defoamerand for a paint with 0% defoamer where different concentration of defoamer whereadded. Standard addition was done for a paint. Matrix effects were investigated bycomparing signal from defoamer in MeOH compared in paint. This study showed thatthe sample preparation of paints should involve dilution in MeOH or water followedby adding of formic acid and centrifugation and filtration to avoid problems in theinstrument. It is possible to identify if a defoamer is present in paint. Quantificationhas not been achieved, due to possible matrix effects and different response whendefoamer is added to the paint before analysis compared to when the defoamer isadded in the manufacturing process.