Why the original trilogy of Star Wars, composed by the episodes IV, V and VI, it become a planetary success? Through the analysis of the narrative and technique structure of the work it is possible to find again some of the winning characteristics of this movie production. To create the saga of Star Wars, Lucas was inspired to anthropologist Joseph Campbell's writings, particularly to the "Hero from the thousand faces", but to technically realize the fantastic world of Star Wars, he created and used some of the more pioneristicis special effects of the '70. The final result was a movie with an incomparable visual and narrative impact. This thesis tries to analyze the tappes that brought Star Wars to become a point of reference for the whole science fiction cinema .