AbstractCronartium pinicauses economic losses especially on Scots pine in northern Europe. Scots pine reacts to rust infection by resin flow. The chemicals enriched in wood afterCronartiuminfection have not been investigated before. We investigated resin acids and mono‐ and sesquiterpenes produced inCronartium‐infected wood.Cronartium‐infected wood was extracted with acetone, and the extractives were analysed by GC‐mass spectrometry (GC‐MS) and compared to those from control wood. Among resin acids, abietic acid, levopimaric acid, palustric acid, dehydroabietic acid and neoabietic acid were the richest (32–68 mg/g) inCronartium‐infected wood. Among monoterpenes, concentration of α‐pinene was the highest (49 mg/g) inCronartium‐infected wood. Concentrations of all monoterpenes and resin acids and most sesquiterpenes were significantly higher (1.3‐ to 108‐fold) inCronartium‐infected wood compared to control wood. In the control wood, the extractive content was greater (1.1‐ to 14‐fold) than in the literature suggesting that the chemical processes were strongly affected by the rust. The results suggest that terpenes and resin acids are produced by the host to protect it fromCronartiumrust.