The invention discloses a novel preparation method for a chirality sulfoxide type compound and salt of the chirality sulfoxide type compound and a crystal form. The preparation method is used for preparing a chirality sulfoxide compound which exists in a single enantiomer form or in a rich enantiomer form in an enantioselective mode. Under the conditions that tartaric acid diamide ligand, titanium complexation and water exist, the same effect that when alkali is added can be achieved without adding the alkali, namely the same enantioselectivity and percent conversion can be achieved. Besides, the invention further provides a novel crystal form of S - ( - ) - omeprazole sodium salt.