EXHIBIT 5(a)

April 8, 2004

E. I. du Pont de Nemours and Company

1007 Market Street

Wilmington, Delaware 19898

Sir/Madam:

Reference is made to the Registration Statement being filed by you with the Securities and Exchange Commission, relating to forty-eight million (48,000,000) shares of E. I. du Pont de Nemours and Company (hereinafter called “the Company”) $0.30 par value Common Stock (“Common Stock”). It is my opinion that:

(a) the Company is duly organized and existing under the laws of the State of Delaware; and

(b) all shares of Common Stock so registered are or will when sold, be legally issued, fully paid and nonassessable.

I hereby consent to the use of this opinion in connection with the above-mentioned Registration Statement.

Very truly yours,

/s/    Stacey J. Mobley        

Stacey J. Mobley

Senior Vice President and Chief Administrative Officer

and General Counsel