AbstractA method is presented which is suitable for the analysis of the individual glucosinolates (GSLs) in seeds and leaves of rapeseed (Brassica napus and B. campestris). By ion exchange at pH 7 with K2SO4as eluans it is possible to investigate also plant tissues with a high content of sucrose such as roots of turnip (B. rapa var. rapa). The same technique is recommended for the analysis of plant material with a low content of GSLs (<10 μmole/g dry matter). The use of Al‐capsules as reaction vessels offer an elegant and inexpensive way for the conversion of GSLs to their corresponding trimethylsilyl derivatives. With methylsilylhexafluorobutyramide (MSHFBA) as donor of the silyl group deterioration of FID‐detectors can be lowered to a minimum de