New series of organosiloxane ferroelectric liquid crystalline materials have been synthesized, and their mesomorphic and physical properties have been characterized. These new series contain bis-siloxane or tris-siloxane unit attached to the flexible alkyl chain end of (2S,3S)-2-chloro-3-methylvalerate. The siloxane molecule induction is helpful to the chiral smectic C (S-C*) formation and chiral S-C* stabilization, and it simultaneously causes the liquid crystal temperature range of chiral S-C* to be broader. The siloxane member is helpful in reducing the smectic C (S-C) transation shift temperature, and the molecule containing tris-siloxane units shows better effect than the bis-siloxane one. The synthesis and characterization of the new FLCs materials which exhibit S-C* phase at room temperature and higher spontaneous polarization are presented.