As previously reported, the unit had been unavailable from distributors for some time, which led to speculation that Apple was preparing to concede defeat and kill the 8-inch cube-shaped computer.
"Cube owners love their Cubes, but most customers decided to buy our powerful Power Mac G4 minitowers instead," Apple vice president Phil Schiller said in a statement.
For the past month and a half, the Cube has grown progressively less plentiful from distributors and retailers, although the machines remained listed as available on Apple's online store up to Tuesday morning.
Although its clear case and small size drew wows when it was introduced at last July's Macworld Expo in New York, sales of the Cube were far below Apple's plans.
With a glut of the Cubes in the hands of distributors and retailers, Apple shipped just 12,000 of the machines in the January-to-March quarter this year, down from the 29,000 units it shipped in the previous quarter. The company said in February that it had expected to sell three times as many Cubes as it had so far.
Apple said in its statement that there is a small chance it will reintroduce an upgraded version of the Cube at some later date but said it has no plans to do so at the time.
An Apple spokesperson declined to comment further.
Guernsey Research analyst Chris LeTocq said Apple had aimed the Cube as an entry point to its professional G4 line, but the market Apple found was limited and largely consisted of upscale consumers.
"People who bought it were the high-end iMac guys," LeTocq said.
But the demise of the Cube does leave a gap in Apple's product line, LeTocq said.
"The question is what is Apple going to have in its line for consumers who want more than an iMac?"
One possibility is that Apple will introduce an all-in-one computer with a flat-panel display at this year's Macworld Expo, happening later this month in New York.
Gartner analyst Mark Margevicius says the discontinuation of Apple's G4 Cube won't significantly hurt the company, but it certainly won't help, either
Bryan, a technician at the Arizona Macintosh Users Group, who preferred not to give his last name, told CNET News.com he saw several machines that needed repairs because of problems with the power switch.
"Good idea, bad design," he said of the Cube, which was designed to turn on and off without a physical button by detecting the electrical current running through the finger of the person using the machine. "I've struggled to get a few of those repaired."
LeTocq also took Apple to task for not clearly stating in its release that it will provide support to those bought a Cube.
"It may be implicit, but frankly you need to be explicit with this type of announcement," LeTocq said.
An Apple representative said the company will continue to offer ongoing support for Cube owners as it does for other discontinued products.