Exhibit 23.1 Consent of Independent Registered Public Accounting Firm We consent to the incorporation by reference in the Registration Statement on Form S-8 (File No. 333-118140) of our reports dated March 15, 2005, with respect to Newpark Resources, Inc.'s consolidated financial statements and Newpark Resources, Inc. management's assessment of the effectiveness of internal control over financial reporting of Newpark Resources, Inc., and the effectiveness of internal control over financial reporting, which were included in Newpark Resources, Inc.'s Annual Report on Form 10-K for the year ended December 31, 2004. /s/ Ernst & Young LLP New Orleans, Louisiana November 9, 2005