We experimentally studied the tunable effects of connective dendritic left-handed metamaterials based on electrorheological fluids. Three influencing factors-the distance of electrodes，the permittivity of embedding media，and the intensity of applied electric fields-are discussed respectively. The experimental results show that the distance of electrodes exhibits an important effect on the transmission peak of the samples. The left-handed transmission peak shifts to lower frequency when the electrorheological fluids infiltrate. Moreover，by changing the intensity of electric field，the left-handed transmission peak can be modulated actively，and the maximum shift is up to 140 MHz.