EXHIBIT 23.1 Consent of Independent Auditors As independent public accountants, we hereby consent to the incorporation by reference in this Post-Effective Amendment No. 1 to the Registration Statement on Form S-8 (No. 333-64231) of our report dated January 15, 1999, included in Syntroleum Corporation's Form 10-K for the year ended December 31, 1998, and to all references to our Firm included in this registration statement. /s/ Arthur Andersen LLP Tulsa, Oklahoma June 17, 1999