We demonstrate a polarization insensitive arrayed-input spectrometer using echelle diffraction grating (EDG) for hyperspectral imaging. The EDG consists of 65 input waveguides and 129 output waveguides, allowing spectral measurements of 65 image pixels at a time when used in combination with a micro-electromechanical system micro mirror array. The spectral resolution reaches 7.8 nm for wavelengths ranging from 1250 to 1700 nm. The measured loss is 2dB, and the crosstalk is lower than 20dB. The 3 μm silicon-on-insulator platform provides the device with polarization insensitive characteristics. The chip size is only 6mm×10mm.