EXHIBIT 5.1



                                 Bryan Cave LLP
                             120 Broadway, Suite 300
                           Santa Monica, CA 90401-2386
                            Telephone: (310) 576-2100
                            Facsimile: (310) 576-2200



                                 August 7, 2002

Tekelec
26580 West Agoura Road
Calabasas, California  91302

            Re:   Tekelec - Registration Statement on Form S-8

Ladies and Gentlemen:

            We have acted as securities counsel for Tekelec, a California
corporation (the "Company"), in connection with the preparation of a
registration statement on Form S-8 (the "Registration Statement") under the
Securities Act of 1933, as amended (the "Act"), to be filed with the Securities
and Exchange Commission (the "Commission") on August 7, 2002, in connection with
the registration under the Act of an aggregate of 7,358,000 shares of Common
Stock, without par value, of the Company (collectively, the "Shares") consisting
of: (i) 5,900,000 shares of Common Stock issuable upon exercise of options
granted or to be granted pursuant to the Company's 1994 Stock Option Plan, (ii)
200,000 shares of Common Stock issuable upon exercise of options granted or to
be granted under the Company's Employee Stock Purchase Plan, (iii) 500,000
shares of Common Stock issuable upon exercise of options granted or to be
granted under the Company's Non-Employee Director Stock Option Plan, (iv)
710,000 shares of Common Stock issuable upon exercise of Nonstatutory Stock
Options granted to officers of the Company and (v) 48,000 shares of Common Stock
which have been issued to officers of the Company pursuant to "employee benefit
plans" as defined in Rule 405 promulgated under the Act (the aforementioned 1994
Stock Option Plan, Employee Stock Purchase Plan, Non-Employee Director Stock
Option Plan, Nonstatutory Stock Options and employee benefit plans are referred
to collectively herein as the "Plans").

            In connection with the preparation of the Registration Statement, we
have made certain legal and factual examinations and inquiries and examined,
among other things, such documents, records, instruments, agreements,
certificates and matters as we have considered appropriate and necessary for the
rendering of this opinion. We have assumed for the purpose of this opinion the
authenticity of all documents submitted to us as originals and the conformity
with the originals of all documents submitted to us as copies, and the
genuineness of the signatures thereon. As to various questions of fact material
to this opinion, we have, when relevant facts were not independently
established, relied, to the extent deemed proper by us, upon certificates and
statements of officers and representatives of the Company.

            Based on the foregoing and in reliance thereon and upon our review
of applicable statutes and case law, it is our opinion that: (i) the Shares have
been duly authorized, (ii) the Shares that have been issued (i.e., 48,000
Shares) are validly issued, fully paid and nonassessable, and (iii) the
remaining Shares (i.e., 7,310,000 Shares), after the Registration Statement
becomes effective and after any post-effective

amendment required by law is duly completed, filed and becomes effective, and
when the applicable provisions of "Blue Sky" and other state securities laws
shall have been complied with, and when the Shares are issued and sold in
accordance with the Plans and the Form S-8 prospectuses to be delivered to
participants in the Plans, will be validly issued, fully paid and
non-assessable.

            We hereby consent to the inclusion of our opinion as Exhibit 5.1 to
the Registration Statement and further consent to the reference to this firm in
the Registration Statement. In giving this consent, we do not hereby admit that
we are in the category of persons whose consent is required under Section 7 of
the Act or the rules and regulations of the Commission thereunder.

            This opinion is rendered solely for your benefit in accordance with
the subject transaction and is not to be otherwise used, circulated, quoted or
referred to without our prior written consent. We are opining herein as to the
effect on the subject transaction only of United States federal law and the
internal (and not the conflict of law) laws of the State of California, and we
assume no responsibility as to the applicability thereto, or the effect thereon,
of the laws of any other jurisdiction.

                                              Very truly yours,

                                              /s/ Bryan Cave LLP

                                              BRYAN CAVE LLP