The total content and pattern of gangliosides were determined in the unfractionated sera of 11 healthy human adults and in isolated lipoproteins. The total content of lipid‐bound sialic acid was 10.5 ± 3.2 nmol/ml serum. The ganglioside profile consisted of more than ten different components. The major ganglioside was GM₃, followed by GD₃, GD_1a, GM₂, GT_1b, MG‐3 (sialosyllactoneotetraosylceramide), GD_1b and GQ_1b. Traces of four additional gangliosides could not be quantified reliably. Ganglioside patterns did not vary in sera taken from healthy adults of different age and sex. Approximately 98% of human serum gangliosides were transported by serum lipoproteins, predominantly by LDL (66%), followed by HDL (25%) and VLDL (7%). The quantitative distribution of individual gangliosides in VLDL and LDL was almost the same as that in the unfractionated serum; some differences existed with the ganglioside profile in HDL.