Following the review concerning the nonenergetic functions of saccharides in plants [Kączkowski, 2002] this review is devoted to the presentation of polysaccharide synthesis breakdown and modification, using available chemical and biological methods, in order to alter the concomitant properties towards the practically required directions. For comparison to starch, as the main plant reserve polysaccharide, other components of this type, obtained at present by the microbial biotechnology methods and applied in clinical, agricultural and nutritional industries, are also shortly reviewed. As variable saccharides are important components of glycosides, some more interesting groups of such compounds are also referred, including cooperating glycosyltransferases (GT) as well as their modification possibilities and application areas; they concern polyketide, flavonoid (anthocyanidin) and cyanogenic glycosides, glucosinolates, and some others.