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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
 Washington, D.C. 20549
 FORM 10-K
 ANNUAL REPORT
PURSUANT TO SECTIONS 13 OR 15(d)
OF THE SECURITIES EXCHANGE ACT OF 1934
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    ANNUAL REPORT PURSUANT TO SECTION 13 OR
15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
 For the fiscal year ended December 31, 2005
 OR
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    TRANSITION REPORT PURSUANT TO SECTION 13
OR 15(d) OF THE SECURITIES EXCHANGE ACT
OF 1934
 For the transition period from                      to
 Commission file number 333-110499-122
 Principal Life Income Fundings Trust 10
 (by Principal Life Insurance Company as depositor)
  Iowa
    
    42-0127290(State or other jurisdiction of
incorporation or organization)
    
    (I.R.S. Employer Identification No.)
 Principal Life Income Fundings Trust 10
c/o Principal Life Insurance Company, as depositor
711 High Street
Des Moines, Iowa 50392-0001
(515) 247-5111
 (515) 247-5111
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TABLE OF CONTENTS  PART IItem 3. Legal ProceedingsItem 4. Submission of Matters to a Vote of Security HoldersPART IIItem 5. Market for Registrants Common Equity, Related Stockholder Matters and Issuer Purchases of Equity SecuritiesPART IIIItem 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder MattersItem 13. Certain Relationships and Related TransactionsPART IVItem 15. Exhibits, Financial Statement Schedules, and Reports on Form 8-KSIGNATURESEXHIBIT INDEXSection 302 CertificationAnnual Statement of ComplianceReport of Independent Registered Public Accounting Firm    Table of Contents  
 PART I
 
 Item 3. Legal Proceedings.
  
 Item 4. Submission of Matters to a Vote of Security Holders.
  
 PART II
 
 Item 5. Market for Registrants Common Equity, Related Stockholder Matters and Issuer Purchases of
Equity Securities.
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PART III
 
 Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder
Matters.
  
 Item 13. Certain Relationships and Related Transactions.
  
 PART IV
 
 Item 15. Exhibits, Financial Statement Schedules, and Reports on Form 8-K.
 Exhibit 31.1
    
    Section 302 Certification.Exhibit 99.1
    
    Indenture Trustee Reports of the Trust  Incorporated herein by
reference to Exhibit 99.1 to the Current Report(s) on Form 8-K filed
by Principal Life Insurance Company on behalf of Principal Life
Income Fundings Trust 10 on May 6, 2005, and to the Current Report(s)
on Form 8-K filed by Principal Life Insurance Company on behalf of
Principal Life Income Fundings Trust 10 on June 8, 2005, and to the
Current Report(s) on Form 8-K filed by Principal Life Insurance
Company on behalf of Principal Life Income Fundings Trust 10 on July
11, 2005, and to the Current Report(s) on Form 8-K filed by Principal
Life Insurance Company on behalf of Principal Life Income Fundings Trust 10
on August 9, 2005, and to the Current Report(s) on Form 8-K filed
by Principal Life Insurance Company on behalf of Principal Life Income Fundings
Trust 10 on September 9, 2005, and to the Current Report(s) on Form 8-K
filed by Principal Life Insurance Company on behalf of Principal Life
Income Fundings Trust 10 on October 4, 2005, and to the Current
Report(s) on Form 8-K filed by Principal Life Insurance Company on
behalf of Principal Life Income Fundings Trust 10 on November 7,
2005, and to the Current Report(s) on Form 8-K filed by Principal
Life Insurance Company on behalf of Principal Life Income Fundings
Trust 10 on December 9, 2005.Exhibit 99.2
    
    Annual Statement of Compliance by Citibank, N.A.Exhibit 99.3
    
    Report of Independent Registered Public Accounting Firm on Compliance.
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##### Table of Contents



SIGNATURES
  PRINCIPAL LIFE INSURANCE COMPANY(Registrant)Date: March 24, 2006
    
    By:
    
    /s/
Karen A. PearstonName: Karen A. PearstonTitle: Second Vice President and Counsel
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##### Table of Contents



EXHIBIT INDEX
 ExhibitNumber
    
    DescriptionExhibit 31.1
    
    Section 302 Certification.Exhibit 99.1
    
    Indenture Trustee Reports of the Trust  Incorporated herein by
reference to Exhibit 99.1 to the Current Report(s) on Form 8-K filed
by Principal Life Insurance Company on behalf of Principal Life
Income Fundings Trust 10 on May 6, 2005, and to the Current Report(s)
on Form 8-K filed by Principal Life Insurance Company on behalf of
Principal Life Income Fundings Trust 10 on June 8, 2005, and to the
Current Report(s) on Form 8-K filed by Principal Life Insurance
Company on behalf of Principal Life Income Fundings Trust 10 on July
11, 2005, and to the Current Report(s) on Form 8-K filed by Principal
Life Insurance Company on behalf of Principal Life Income Fundings
Trust 10 on August 9, 2005, and to the Current Report(s) on
Form 8-K filed by Principal Life Insurance Company on behalf of
Principal Life Income Fundings Trust 10 on September 9, 2005, and to the Current Report(s) on Form 8-K
filed by Principal Life Insurance Company on behalf of Principal Life
Income Fundings Trust 10 on October 4, 2005, and to the Current
Report(s) on Form 8-K filed by Principal Life Insurance Company on
behalf of Principal Life Income Fundings Trust 10 on November 7,
2005, and to the Current Report(s) on Form 8-K filed by Principal
Life Insurance Company on behalf of Principal Life Income Fundings
Trust 10 on December 9, 2005.Exhibit 99.2
    
    Annual Statement of Compliance by Citibank, N.A.Exhibit 99.3
    
    Report of Independent Registered Public Accounting Firm on Compliance.
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