The molecular geometry of the racemate rrcrr1~-4,6-dirnethyl trimethylene sulfite has been studied in the gas phase by electron diffraction. Six trial conformations were examined by least squares fitting of the intensity data. A significance test applied to the fits obtained for each of the six static models tested indicate that the best single representation of the molecule has a chair conformation, although a mixture containing other conformations could not be definitely eliminated. It was not possible to conclusively discriminate between an axial or an equatorial S==O bond, although the axial position is favored. La geometrie moleculaire du rrarls dimethyl-4,6 trimethylene sulfite racemique a Cte etudiee en phase gazeuse par diffraction electronique. Six conformations ont ete testees par la methode des ajustements aux moindres carres sur les donnees des intensites. Un test significatif applique aux ajustements obtenus sur chacun des six modeles statiques montre que I'unique et la meilleure representation de la molecule possede une conformation chaise, bien qu'un melange d'autres types de conformations n'ait pu Ctre ecarte definitivement.