Hepatocellular carcinoma (HCC) development entails changes in liver metabolism. Current knowledge on metabolic perturbations in HCC is derived mostly from case‐control designs, with sparse information from prospective cohorts. Our objective was to apply comprehensive metabolite profiling to detect metabolites whose serum concentrations are associated with HCC development, using biological samples from within the prospective European Prospective Investigation into Cancer and Nutrition (EPIC) cohort (>520 000 participants), where we identified 129 HCC cases matched 1:1 to controls. We conducted high‐resolution untargeted liquid chromatography‐mass spectrometry‐based metabolomics on serum samples collected at recruitment prior to cancer diagnosis. Multivariable conditional logistic regression was applied controlling for dietary habits, alcohol consumption, smoking, body size, hepatitis infection and liver dysfunction. Corrections for multiple comparisons were applied. Of 9206 molecular features detected, 220 discriminated HCC cases from controls. Detailed feature annotation revealed 92 metabolites associated with HCC risk, of which 14 were unambiguously identified using pure reference standards. Positive HCC‐risk associations were observed for N1‐acetylspermidine, isatin, p‐hydroxyphenyllactic acid, tyrosine, sphingosine, l,l‐cyclo(leucylprolyl), glycochenodeoxycholic acid, glycocholic acid and 7‐methylguanine. Inverse risk associations were observed for retinol, dehydroepiandrosterone sulfate, glycerophosphocholine, γ‐carboxyethyl hydroxychroman and creatine. Discernible differences for these metabolites were observed between cases and controls up to 10 years prior to diagnosis. Our observations highlight the diversity of metabolic perturbations involved in HCC development and replicate previous observations (metabolism of bile acids, amino acids and phospholipids) made in Asian and Scandinavian populations. These findings emphasize the role of metabolic pathways associated with steroid metabolism and immunity and specific dietary and environmental exposures in HCC development. What's new? Changes in liver function precede the development of hepatocellular carcinoma (HCC). Many of these changes can be detected in the blood, as can biomarkers related to lifestyle or environmental exposures that may affect HCC risk. In this study, based on a large, prospective observational cohort, the authors used high resolution mass spectrometry‐based metabolomics to identify alterations in circulating levels of 92 metabolites associated with HCC risk, 14 of which could be annotated with high confidence and some of which were observed up to 10 years prior to diagnosis. These results offer insight into early metabolic perturbations and mechanisms leading to this deadly cancer.