Label

Element

Value

Risk/Return:

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Prospectus Date

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Mar. 01, 2011

Diversified International Fund (Prospectus Summary): | Diversified International Fund

Risk/Return:

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Risk/Return, Heading

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DIVERSIFIED INTERNATIONAL FUND    

Supplement Text

ck0000898745_SupplementTextBlock

Supplement dated June 16, 2011

to the Class A, Class B, and Class C Prospectus

for Principal Funds, Inc.

dated March 1, 2011

(as supplemented on March 14, 2011 and March 15, 2011)  

This supplement updates information currently in the Prospectus. Retain this supplement with the  

Prospectus.  

Add the following under the Performance heading, just above the Total Returns as of December 31 each  

year heading:  

Effective June 30, 2011, the benchmark will change. The Investment Advisor and Sub-Advisor believe the  

MSCI EAFE Index NDTR D is more widely used for funds in the foreign large blend category than the  

MSCI ACWI Ex-US Index.  

Add the following to the Average Annual Total Returns table:   

Diversified International Fund | Class A

Risk/Return:

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Trading Symbol

dei_TradingSymbol

PRWLX

Diversified International Fund | Class B

Risk/Return:

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Trading Symbol

dei_TradingSymbol

PRBWX

Diversified International Fund | Class C

Risk/Return:

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Trading Symbol

dei_TradingSymbol

PDNCX

Diversified International Fund | MSCI EAFE Index NDTR D

Risk/Return:

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Average Annual Returns, Label

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MSCI EAFE Index NDTR D (reflects no deduction for fees, expenses, or taxes)

Average Annual Returns, 1 Year

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7.75%

Average Annual Returns, 5 Years

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2.46%

Average Annual Returns, 10 Years

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3.50%