First introduced in 1978, Lego space sets featured spaceships and astronauts. It is also one of the biggest and most expansive toy sets that Lego has produced. It has about 200 individual sets, which when connected formed one big outer space set. The first of the Lego space sets that were produced were considered to be a great leap forward in terms of design. It has since become one of the most loved and cherished Lego products putting it upon the same pedestal as the Lego train sets, pirates Lego themed sets and the medieval castle sets. In comparison to the former space set releases which included the Rocket Base, Space Rocket and the Moon Landing sets, the newer and better themed Space and Mars showcased new building techniques as well as Lego parts that were previously unseen. Even though the traditional Lego bricks were still present in these new sets, they also had some finer details, which enabled more multi-purpose space vehicles and smoother looking battleships.

In the early space sets there were certain oddities such as the use of a steering wheel to drive the spacecraft and even though it lacks any on board pilot protection except that of the space suit, it was still fancy enough to spark the imaginations of kids back then. From battleships and the basic 4 wheeled vehicles, the theme further developed and was often said to be following the trends of science fiction movies prevalent at that time. As their development continued, the vehicle designs became more advanced as well. The addition of Lego minifigures, robots, space bases, buggies, as well as, larger battleships soon followed. These early sets, though perhaps rather humble when compared to today's standards, were the most modern amongst other sci-fi inspired toys during that time. They were simple yet very charming toys that kids adored. Eventually, gray become a major color for this theme which well fitted to its very futuristic and utilitarian theme. There were also more building base plate type Lego parts, in that color, that were being made. More often than not, these gray parts were paired with green, which can be seen in the space ships windows. Other dominant colors also included yellow and blue.

The most recent of space Lego sets would be Life on Mars, which included interaction between the human Lego minifigs and the Martian ones. It shows a very peaceful co-existence between both races and was released during a time when there was much interest and curiosity surrounding the red planet and the possibility of other beings living on it. The new set incorporated what was thought to be very reminiscent of a Martian landscape, thus the sand that was colored in green, red and purple. Though not as colorful as the previous sets, it did feature a first, which are the transparent brown windows for the battleships. Following the release of Life on Mars, 2007 saw the debut of Mars Mission, which is the second installment in the series of Mars related sets. Unlike the early ones where the humans and extra terrestrials existed peacefully, these sets saw them being pitted against each other which was what the children did with the first set anyway. Up to date Lego space sets are sure to be released in keeping with the advances in today's space technology