Diarylethene switches are synthetic organic molecules which contain heterocyclic rings connected with double bond and they have photochromic properties. During photochromic reaction, six membered ring is created and position of double bonds is changed. Photochromism^[1,2] can be defined as a reversible phototransformation of a molecular switches between two forms of isomers (closed and open) possessing different absorption spectra. The diarylethene molecular switches with crown-ether units 1 can exhibit novel photochromic and complexation properties due to special position of the crown-ether over central double bond. The crown-ether unit is very flexible and can allow E- and Z- geometric isomers of the dithienylethene molecular switches. The equilibrium between these two geometric isomers can be shifted to the Z- isomer due to complexation with metal ions.