Exhibit (b)

                             Loomis Sayles Funds I
                           Section 906 Certification

   In connection with the report on Form N-CSR for the period ended March 31,
2006 for the Registrant (the "Report"), the undersigned each hereby certifies
to the best of his knowledge, pursuant to section 906 of the Sarbanes-Oxley Act
of 2002, that:

   1. the Report complies with the requirements of Section 13(a) or 15(d) of
the Securities and Exchange Act of 1934, as applicable; and

   2. the information contained in the Report fairly presents, in all material
respects, the financial condition and results of operations of the Registrant.

By:                                     By:
President & Chief Executive Officer     Treasurer
Loomis Sayles Funds I                   Loomis Sayles Funds I

/s/ Robert J. Blanding                  /s/ Michael C. Kardok
- --------------------------------------  --------------------------------------
Robert J. Blanding                      Michael C. Kardok

Date: May 24, 2006                      Date: May 24, 2006

A signed original of this written statement required by Section 906, or other
document authenticating, acknowledging, or otherwise adopting the signature
that appears in typed form within the electronic version of this written
statement required by Section 906, has been provided to the Loomis Sayles Funds
I, and will be retained by the Loomis Sayles Funds I and furnished to the
Securities and Exchange Commission (the "Commission") or its staff upon request.