Glycoarrays have become a powerful platform to investigate the interactions of many biological events involving carbohydrates. The carbohydrates immobilization on the surface of the substrates is a key step of glycoarray fabrication. Plenty of strategies have been applied to the immobilization process. Herein a protocol for the synthesis of oligonucleotide glycomimetic conjugates is proposed. The resulting molecules are immobilized by hybridization on a DNA microarray (DNA-directed immobilization; DDI). DDI has been proved to be a very efficient and site-selective. This protocol provides detailed procedures for the preparation of fluorescent oligonucleotide trigalactosylmimetic conjugates and for the preparation of carbohydrate microarrays by DDI on glass slides.