This paper presents a 4-bit D-band SiGe vector modulator phase shifter (VMPS). A novel transmission line-based delay line topology is used to generate differential quadrature signals that are weighted by 4 VGAs and cascaded with a buffer amplifier, achieving wide bandwidth, moderate gain, and low power consumption. The VMPS achieves 1.5 dB peak average gain with a 3-dB bandwidth from 110 -145 GHz. The peak RMS amplitude and phase errors are 1.2 dB and 8.5∘, respectively, and the circuit consumes 20.3 mW of average DC power from a 1.5 V supply. To the authors best knowledge, the presented D-Band vector modulator phase shifter achieves the widest fractional bandwidth of any mm-Wave vector modulator phase shifter implemented in silicon.