A method of linking nucleosides with a siloxane bridge comprising reacting a 3'-silylated-5'-protected nucleoside with an unprotected nucleoside is disclosed. The silylated and unprotected nucleosides may be either monomeric nucleosides or the terminal nucleosides of an oligonucleotide or oligonucleotide analog. A method of synthesizing an oligonucleotide analog having siloxane internucleoside linkages is also disclosed. The method of synthesis comprises silylating a 5'-protected nucleoside with a bifunctional silylating reagent to form a 3'-silylated nucleoside, reacting the silylated nucleoside with an unprotected nucleoside in the presence of a base catalyst and repeating these steps to form an oligonucleotide analog. A modified solid phase synthesis method for preparing an oligonucleotide analog having siloxane internucleoside linkages is also disclosed.