Tuning performance of a chiral layer using varactor diodes is presented here. The chiral structure consists of an array of metallic long helices fabricated in parallel on a PCB. The helices have the same handedness, sub-wavelength diameter, pitch, and spacing in the array. Varactor diodes are incorporated into the array to tune array cross-polarized transmission response, a qualitative measure of the effective tuned chirality. Each helix is connected to one of its neighboring helices through a set of varactors placed between them. Array has one varactor per one helix pitch. The tuning performance of the chiral array transmissivity is measured over frequency band of 5.5–12 GHz with the bias voltage sweeping from 1 to 15 V. Voltage tuning changes each varactor capacitance from 0.9 to 0.13 pF. This results in ${\sim} 50\hbox{\%}$ increase in the cross-polarization peak frequency, changing it from 6 to 9 GHz, for a linear polarization incidence perpendicular to the helices. Tuning rotates the transmitted wave polarization ellipse by ${\sim} 15^{\circ}$ .