Current DNA extraction methods for parasites are labour-intensive and usually involve several steps, increasing the potential for cross-contamination. We describe here a closed-tube DNA extraction procedure based upon the use of a thermostable proteinase that enabled sensitive amplification of target loci from parasites from diverse lineages including Apicomplexa, Sarcomastgophora and Nematoda. Moreover, this procedure is not subject to cross-contamination and is readily adaptable to automation.