The film starts as Buddha (Field Cate) and his owner, Sam (Nolan Gould), are star-gazing. As a shooting star passes, Sam makes a wish that he can touch the moon. The next day is the day of his school field trip to Vision Enterprises to watch a test launch of the Vision 1 space craft. However, since no pets are allowed to go, he has to leave Buddha at home. Buddha meets up with his siblings, Budderball (Josh Flitter), RoseBud (Liliana Mumy), B-Dawg (Skyler Gisondo), and MudBud (Henry Hodges), and invites them to come with him to go to see the test launch. They hide in the school bus, which soon arrives at the Vision Enterprises. The dogs go to a space-suit machine and put on space-suits before following the students, who are being led by Dr. Finkel (Kevin Weisman). The dogs get aboard the space shuttle Vision 1. At Mission Control in the Vision enterprises, Pi (Bill Fagerbakke) confirms they are ready for launch. Meanwhile, the dogs take a close look around until they are sealed in the shuttle, which prepares for launch. Astro (Ali Hillis), who will be piloting the shuttle from Earth, launches the shuttle, and it flies to space.
At Mission Control, the humans realize the third tank of gas in the shuttle was never filled. With ten hours until the gas runs out, they look for solutions. They eventually decide to pilot the space craft to the old R.R.S.S. (Russian Research Space Station). They contact the cosmonaut living in the space station, named Yuri (Diedrich Bader), telling him to refuel the Vision 1. As Vision 1 connects to the space station, the dogs decide to explore the space station, and they meet a dog called Spudnick (Jason Earles) who is under the care of Yuri. Spudnick explains that Yuri is quite content to stay in space, yet he wishes to go home. Yuri finds the dogs and becomes happy because the buddies can keep them company. The buddies are trapped in the kitchen, and are saved later by Spudnick. After Yuri connects the fuel hose to the Vision 1, the fuel starts to leak from the hose. Meanwhile, the buddies and Spudnick rush back to Vision 1 to escape. Yuri activates lock-down to trap the dogs. They manage to get to the Vision 1. Yuri tries to stop them, banging on the control switches. However, sparks drop on the fuel, causing an explosion. The dogs escape from the R.R.S.S. as it explodes. Yuri barely escapes using the "Cosmo-pod escape vessel".
The Vision 1 travels to the moon. Soon after, the Vision 1 approaches and lands on the moon (Before this event had occurred, B-Dawg had mistaken the moon for the "Death Star"). They soon begin to get out of the Vision 1 and walk around the area within the place they had landed. Mission Control finds that the sounds from their space helmets happen to be soft barks, and conclude they are golden retriever puppies, and this is broadcast on the news. The children find out through the news ("We're live at Vision Enterprises, where quite a furry tale is unfolding. It seems five golden retriever puppies have been accidentally launched into space."). The dogs, while on the moon, meet a ferret named Gravity (Amy Sedaris), who is their mission control assistant. But since their only communication is from audio, they don't know he's a ferret. He orders them to get back on the Vision 1.
When returning to Earth, the path is changed by an unworthy Dr. Finkle. The path's telemetry is reverted into a meteor shower. The "auto-avoidance system" takes control of the Vision 1, rotating and shifting heavily between every meteor in its path. However, the Vision 1's data communications antenna is busted to the right when it becomes struck by a meteor. Budderball is sent to repair the antenna by doing a space walk outside of the Vision 1. At Mission Control, the adults are puzzled about the change of the telemetry course of the Vision 1 when Sam accuses Dr. Finkle of changing the path. As Dr. Finkle denies it, Pi uses the security camera to confirm that Dr. Finkle was indeed at the desk at 7:49pm, the time when the telemetry course was changed. As Dr. Finkle is taken away by security, Sam approaches Dr. Finkle and calls him "Dr. Stinkle."
The mission control center receives Yuri's distress signal in the Cosmo-pod before the Vision 1 enters the atmosphere through the blackout zone. They wait 4 minutes till' they arrive, but they arrive early. The Vision 1 ends it's mission by slowing down on the take-off strip. The dogs find out Gravity is a ferret, and so that Budderball replies he is related to skunks. Yuri crashes his pod, and is rescued by some soldiers, telling them he comes from space.
Pi awards the dogs wings of true heroism, with their title as "Space Buddies". They review what they did (Budderball was taught how to eat his vegetables from the trip). Once at home, Buddha gives Sam a moon rock he had taken from his journey, fulfilling his wish of touching the moon. The film ends with Spudnick back at home with his old owner, Sasha, saying, "It is the journey and friendship that matters the most."
- Bill Fagerbakke as Pi
- Diedrich Bader as Yuri
- Kevin Weisman as Dr. Finkle
- Lochlyn Munro as Slats Bentley
- Ali Hillis as Astro Spalding
- Pat Finn as Bill Wolfson
- Nolan Gould as Sam
- Wayne Wilderson as Tad Thompson
- C. Ernst Harth as Guard at the gate to HQ
- Reese Schoeppe as Sasha
- Nico Ghisi as Bartleby Livingston
- Quinn Lord as Pete
- Gig Morton as Billy
- Sophia Ludwig as Alice
- Michael Teigan as Deputy Dan
- Skyler Gisondo as B-Dawg
- Field Cate as Buddha
- Liliana Mumy as RoseBud
- Henry Hodges as MudBud
- Josh Flitter as Budderball
- Amy Sedaris as Gravity, a Black-footed Ferret
- Jason Earles as Spudnick, a Bull Terrier