Exhibit 99.1

CONSENT OF DIRECTOR NOMINEE

In connection with the filing by Apollo Strategic Growth Capital III of the Registration Statement on Form S-1 with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Securities Act”), I hereby consent, pursuant to Rule 438 of the Securities Act, to being named as a nominee to the board of directors of Apollo Strategic Growth Capital III in the Registration Statement and any and all amendments and supplements thereto. I also consent to the filing of this consent as an exhibit to such Registration Statement and any amendments thereto.

Dated: March 22, 2021

/s/ Henrique De Castro

Name: Henrique De Castro