Exhibit 5.1

		140 Scott Drive
		Menlo Park, California 94025
		Tel: +1.650.328.4600 Fax: +1.650.463.2600
		www.lw.com
		FIRM / AFFILIATE OFFICES
		Abu Dhabi		Moscow
		Barcelona		Munich
		Beijing		New Jersey
		Brussels		New York
		Chicago		Orange County
		Doha		Paris
		Dubai		Riyadh
		Frankfurt		Rome
		Hamburg		San Diego
		Hong Kong		San Francisco
March 28, 2011		Houston		Shanghai
		London		Silicon Valley
		Los Angeles		Singapore
		Madrid		Tokyo
		Milan		Washington, D.C.
Ellie Mae, Inc.		File No. 042829-0009
4155 Hopyard Road, Suite 200
Pleasanton, California 94588

Ladies and Gentlemen:

We have acted as special counsel to Ellie Mae, Inc., a Delaware corporation (the “Company”), in connection with the registration statement on Form S-1 filed by the Company with the Securities and Exchange Commission (the “Commission”) on April 30, 2010 (Registration No. 333-166438) (as amended, the “Registration Statement”) under the Securities Act of 1933, as amended (the “Act”). The Registration Statement relates to the registration of 8,625,000 shares of common stock of the Company, par value $0.0001 per share (the “Common Stock”), 5,000,000 shares of which will be newly issued shares offered by the Company (the “Company Shares”), 2,500,000 shares of which are being offered by certain stockholders of the Company (the “Selling Stockholder Primary Shares”) and 1,125,000 shares of which may be purchased by the underwriters pursuant to an option to purchase additional shares granted to the underwriters by certain stockholders of the Company (the “Selling Stockholder Option Shares,” and together with the Selling Stockholder Primary Shares, the “Selling Stockholder Shares”). The Company Shares and the Selling Stockholder Shares are referred to herein collectively as the “Shares.” The term “Shares” shall include any additional shares of Common Stock registered by the Company pursuant to Rule 462(b) under the Act in connection with the offering contemplated by the Registration Statement. This opinion is being furnished in connection with the requirements of Item 601(b)(5) of Regulation S-K under the Act, and no opinion is expressed herein as to any matter pertaining to the contents of the Registration Statement or related prospectus (the “Prospectus”), other than as expressly stated herein with respect to the issue of the Company Shares. Various matters concerning the Selling Stockholder Shares are addressed in the opinion of Richards, Layton and Finger, P.A., which has been separately provided to you. We express no opinion with respect to those matters.

March 28, 2011

Page 2

As such counsel, we have examined such matters of fact and questions of law as we have considered appropriate for purposes of this letter. With your consent, we have relied upon certificates and other assurances of officers of the Company and others as to factual matters without having independently verified such factual matters. We are opining herein as to the General Corporation Law of the State of Delaware (the “DGCL”), and we express no opinion with respect to any other laws.

Subject to the foregoing and the other matters set forth herein, it is our opinion that, as of the date hereof, when the Company Shares shall have been duly registered on the books of the transfer agent and registrar therefor in the name or on behalf of the purchasers, and have been issued by the Company against payment therefor in the circumstances contemplated by the form of underwriting agreement most recently filed as an exhibit to the Registration Statement, the issue and sale of the Company Shares will have been duly authorized by all necessary corporate action of the Company, and the Company Shares will be validly issued, fully paid and nonassessable. In rendering the foregoing opinion, we have assumed that the Company will comply with all applicable notice requirements regarding uncertificated shares provided in the DGCL.

This opinion is for your benefit in connection with the Registration Statement and may be relied upon by you and by persons entitled to rely upon it pursuant to the applicable provisions of the Act. We consent to your filing this opinion as an exhibit to the Registration Statement and to the reference to our firm in the Prospectus under the heading “Legal Matters.” We further consent to the incorporation by reference of this letter and consent into any registration statement or post-effective amendment to the Registration Statement filed pursuant to Rule 462(b) with respect to the Shares. In giving such consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Act or the rules and regulations of the Commission thereunder.