Label

Element

Value

Risk/Return:

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Document Type

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Other

Document Period End Date

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Jun. 14, 2013

Registrant Name

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PRINCIPAL FUNDS INC

Central Index Key

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0000898745

Amendment Flag

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false

Document Creation Date

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Jun. 14, 2013

Document Effective Date

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Jun. 14, 2013

Prospectus Date

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Dec. 28, 2012

PFI Prospectus Class ACP

Risk/Return:

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Supplement [Text Block]

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Supplement dated June 14, 2013

to the Classes A, C, and P Shares Prospectus

for Principal Funds, Inc.

dated December 28, 2012

(as supplemented on February 8, 2013, March 15, 2013 and April 29, 2013)

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

FUND SUMMARIES

PFI Prospectus Class ACP | Global Multi-Strategy Fund [Member]

Risk/Return:

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Risk/Return [Heading]

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Global Multi-Strategy Fund

Strategy [Heading]

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Under the Principal Investment Strategies heading, delete the paragraph that begins with "Equity Long/Short" and substitute:

Strategy Narrative [Text Block]

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Equity Long/Short. This strategy provides long and short exposure to a diversified portfolio of U.S and non-U.S. equities which involves simultaneously investing in equities (i.e., investing long) the sub-advisor expects to increase in value (securities the sub-advisor believes are undervalued) and either selling equities (i.e., short sales or short selling) the sub-advisor expects to decrease in value (securities the sub-advisor believes are overvalued) or hedging equity market exposure in another way (i.e., by using derivatives such as futures or options). Long/short equity expresses industry views by emphasizing certain industries and it also seeks to exploit pricing inefficiencies between related equity securities. An example of exploiting pricing inefficiencies between related equity securities is building a portfolio containing long positions in the strongest companies of several industries and taking short positions in companies showing signs of weakness in the corresponding industries. This strategy has available two methods of analysis: fundamental analysis, a method of security analysis that involves examining a company's financial statements and operations, especially sales, earnings, products, management and competition and quantitative analysis, a method of security analysis that involves use of mathematical models to examine a company's measurable characteristics such as revenue, earnings, margins and market share.