A radar signal processing apparatus is disclosed which includes: time-series phase data generating section 3 generating time-series phase data in a range bin of interest based on a range profile indicating, for each range bin, a phase of a reflected wave of a radio wave from a target; phase-rotation-amount time-series data generating section 4 that divides the time-series phase data into segments of a predetermined time length, calculates an amount of phase rotation that occurs in the segments, and generates time-series data on the amount of phase rotation; pattern matching section 6 that performs pattern matching between the generated time-series data on the amount of phase rotation and a template of time-series data on the amount of phase rotation that is defined by a distance and a moving speed; and speed detection section 7 that detects the moving speed of the target based on a result of the pattern matching.