Two kinds of cross-linked polyether solid electrolytes (CPESE) with high ionic conductivity (a) of 8.0x10(-5) S cm(-1) (25 degrees C, for double ionic conducting CPESE2) or 4.0x10(-6) S cm(-1) (30 degrees C, for single ionic conducting CPESE1) were obtained by polymerizing alpha,omega-bismethacryloyl capped poly(ethylene glycol) (BMAPEG) after complexing with LiClO4 or copolymerizing BMAPEG with salt of methacrylic acid (MAAM), respectively. In the mean time, the CPESE based anhydrous electrorheological (ER) fluids with relatively high activity were directly synthesized by inverse suspension polymerization of BMAPEG after complexing with LiClO4 or of BMAPEG with MAAM. The influences of structure of CPESE on their conductivity and properties for ER fluids based on them were studied. The results showed that maximum a occurred at an optimum molecular weight of poly(ethylene glycol) segment (M-PEG) as well as a certain value of [Li+]/[EO] or [MAAM]I[EO], while a decreased with increasing functionality of BMAPEG (f). For ER fluids containing CPESE2, yield stress ( tau(s),) increased with f while tau(s) showed a maximum value at a certain [Li+]/[EO]. Leak current density (J) increased with increasing [Li+]/[EO] or with decreasing f. A maximum J occurred with change of MPEG For ER fluids containing CPESE1, both tau(s) and J showed a maximum value with increasing M-PEG or [MAAM]/[EO], while tau(s) and J decreased with increasing f. tau(s) hardly depended on the type of its counterion, while J decreased in the following counterion order : K+ approximate to Li+ > Na+.