Abstract: The invention relates to a sample processing system for a plasma spectrometer for analysing viscous samples, and samples insoluble at room temperature. The system comprises a tray with tubes containing the sample, a heating block comprising a thermoregulation switch and means for collecting the sample from tubes. Said means are connected to a transfer tube transferring the solution that is pumped down by a peristaltic pump. The peristaltic pump is controlled by a controller box and comprises a first pump tubing of internal diameter &phgr; and a second pump tubing of internal diameter &phgr;′. A sample introduction system is fed by the peristaltic pump and contains a nebulizer and a spray chamber placed in a thermoregulated box. According to the invention, said sample processing system is thermoregulated, temperatures are variable and can be selected according to the nature of the sample to analyse.