EXHIBIT
      5.1
    
    [LETTERHEAD
      OF RUTAN & TUCKER, LLP]
    
    Rutan
      & Tucker, LLP
    611
      Anton
      Boulevard, Suite 1400
    Costa
      Mesa, California 92626
    
    July
      27,
      2007
     
    Pacific
      Ethanol, Inc.
    400
      Capitol Mall, Suite 2060
    Sacramento,
      California  95814
    
    Re:    Registration
      Statement on Form S-3
    
    Ladies
      and Gentlemen:
     
    We
      have
      acted as counsel to Pacific Ethanol, Inc., a Delaware corporation (the
“Company”), in connection with the pre-effective Amendment No. 1 to the
      Registration Statement on Form S-3 to which this opinion is an exhibit (the
      “Registration Statement”), including a prospectus (the “Prospectus”), as
      supplemented from time to time by one or more prospectus supplements (each
      a
“Prospectus Supplement”), which provides for the registration by the Company
      of:
     
    
      
          
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               shares
                of its common stock, $0.001 par value per share (“Common Stock”);
                and 
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               warrants
                to purchase Common Stock
                (“Warrants”). 
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    The
      Common Stock and Warrants are being registered for offering and sale from time
      to time pursuant to Rule 415 under the Securities Act of 1933, as amended
      (the “Securities Act”), at an aggregate public offering price not to exceed
      $250,000,000.  The Registration Statement provides that the Common
      Stock and Warrants may be offered in amounts, at prices and on terms to be
      set
      forth in one or more Prospectus Supplements.
     
    In
      connection with rendering this opinion, we have examined and relied upon the
      Registration Statement and related Prospectus, the Company’s Certificate of
      Incorporation, as on file with the Secretary of State of the State of Delaware
      (the “Certificate of Incorporation”); the Company’s Bylaws, as amended and
      restated to the date hereof, as they appear in the minute book of the Company
      (the “Bylaws”); and such other original instruments, documents and records that
      we deemed relevant and necessary for the basis of our opinion hereinafter
      expressed. In such examination, we have assumed the genuineness of all
      signatures and the authenticity of all documents submitted to us as originals
      and the conformity to the originals of all documents submitted to us as
      copies.
     
    On
      the
      basis of the foregoing and in reliance thereon, and subject to the
      qualifications hereinstated, we are of the opinion that:
     
    1.           With
      respect to the Common Stock, offered under the Registration Statement (the
      “Offered Common Stock”) provided, that (i) the Registration Statement and any
      required post-effective amendment thereto have all become effective under the
      Securities Act and the Prospectus and any and all Prospectus Supplements
      required by applicable laws have been delivered as required by such laws, (ii)
      the issuance of the Offered Common Stock has been duly authorized by all
      necessary corporate action on the part of the Company, (iii) the issuance and
      sale of the Offered Common Stock does not violate any applicable law or the
      Certificate of Incorporation or the Bylaws or result in a default under or
      breach of any agreement or instrument binding upon the Company and complies
      with
      any applicable requirement or restriction imposed by any court or governmental
      body having jurisdiction over the Company, and (iv) the certificates for the
      Offered Common Stock have been duly executed by the Company, countersigned
      by
      the transfer agent therefor and duly delivered to the purchasers thereof against
      payment therefor, then the Offered Common Stock, when issued and sold as
      contemplated in the Registration Statement, the Prospectus and the related
      Prospectus Supplements and in accordance with any applicable duly authorized,
      executed and delivered purchase, underwriting or similar agreement, or upon
      exercise of any Offered Warrants (as defined below) in accordance with their
      terms, will be duly authorized, validly issued, fully paid and
      non-assessable.
     
    
    2.           With
      respect to the Warrants offered under the Registration Statement (the “Offered
      Warrants”), provided, that (i) the Registration Statement and any required
      post-effective amendment thereto have all become effective under the Securities
      Act and the Prospectus and any and all Prospectus Supplements required by
      applicable laws have been delivered as required by such laws, (ii) the issuance
      of the Offered Warrants has been duly authorized by all necessary corporate
      action on the part of the Company, (iii) the issuance and sale of the Offered
      Warrants does not violate any applicable law or the Certificate of Incorporation
      or the Bylaws or result in a default under or breach of any agreement or
      instrument binding upon the Company and complies with any applicable requirement
      or restriction imposed by any court or governmental body having jurisdiction
      over the Company, and (iv) the Offered Warrants have been duly executed and
      delivered by the Company and authenticated by the warrant agent therefore
      pursuant to the applicable warrant agreement and duly delivered to the
      purchasers thereof against payment therefor, then the Offered Warrants, when
      issued and sold as contemplated in the Registration Statement, the Prospectus
      and the related Prospectus Supplements and in accordance with any applicable
      duly authorized, executed and delivered purchase, underwriting or similar
      agreement, will be legally valid and binding obligations of the Company,
      enforceable against the Company in accordance with their terms, except as may
      be
      limited by bankruptcy, insolvency, reorganization, moratorium or similar laws
      relating to or affecting creditors’ rights generally (including, without
      limitation, fraudulent conveyance laws), and by general principles of equity
      including, without limitation, concepts of materiality, reasonableness, good
      faith and fair dealing and the possible unavailability of specific performance
      or injunctive relief, regardless of whether considered in a proceeding in equity
      or at law.
     
    This
      opinion is limited to the General Corporation Law of the State of Delaware
      (“DGCL”), including the statutory provisions of the DGCL, all applicable
      provisions of the Constitution of the State of Delaware and all reported
      judicial decisions interpreting these laws, and federal law, exclusive of state
      securities and blue sky laws, rules and regulations.
     
    We
      hereby
      consent to the use of our name under the caption “Legal Matters” in the
      prospectus forming a part of the Registration Statement and to the filing of
      this opinion as Exhibit 5.1 to the Registration Statement.  In giving
      this consent, we do not admit that we are within the category of persons whose
      consent is required under Section 7 of the Securities Act, or the General Rules
      and Regulations of the Securities and Exchange Commission.