Not only was the episode entitled "Gulliver's Gigantic Goof" Green Arrow's only appearance on any of the various versions of SuperFriends, but it was his only appearance on television, period, until the debut of Justice League Unlimited over three decades later in 2004. Since then, he has made numerous television appearances, both animated in JLU, The Batman and Batman: The Brave and the Bold and live action in Smallville.
Many of the so-called villains on the first incarnation of SuperFriends were not truly evil, but simply misguided. Their intentions were always noble, but their efforts to improve the human condition inevitably backfired, endangering the entire planet and requiring the intervention of the Justice League. After our heroes saved humanity they would then impart a valuable moral lesson to the impressionable youth of America.
One such well meaning scientist was Dr. Hiram Gulliver. It was his intent to alleviate world hunger and over population by shrinking everyone in the world down to a height of about two inches. Rather than proposing his plan to the governments of the world or the United Nations, he just goes ahead and starts shrinking people. In the course of attempting to stop Gulliver, the core group of SuperFriends, Superman, Wonder Woman, Aquaman, Batman and Robin, manage to get themselves shrunken and captured. It's then up to none other than Green Arrow, despite ending up shrunken himself, to save the SuperFriends and put a stop to Gulliver's scheme. First, though, he finds time to take a side trip to "Bornego," which appears to be somewhere in Africa, to rescue a pair of animal photographers from "giant" ants with the aid of his trusty trick arrows, as seen in this clip.
The voice of Green Arrow was provided by regular SuperFriends cast member Norman Alden, who also voiced Aquaman.
This one appearance doesn't really show much of the Green Arrow that I've come to know and love over the years, but obviously my eight year old self must have seen something there that appealed to me and would lead me to seek out Green Arrow's adventures in the comics. Say what you will about SuperFriends, and, truth be told, it really wasn't very good, but I apparently do owe them that.