A novel voltage-controlled variable optical attenuator based on a polymeric planar lightwave circuit (PLC) is demonstrated. The fabricated variable attenuator shows 30dB attenuation with only 80mW electrical input power at 1.55 mum. The polarisation dependences at 0 and 10dB attenuations are 0.2 and 1dB, respectively. The rise and fall times are less than 5ms.