[Problem] To provide a biaxially oriented polypropylene film that can achieve excellent voltage resistance and reliability at high temperatures when used in high-voltage capacitors, and that achieves both increased rigidity and thermal dimensional stability suitable for use in capacitors etc. [Solution] Disclosed is a biaxially oriented polypropylene film, wherein: the puncture strength of the film is 70 g/µm or greater; and the heat shrinkage rate in the film width direction is 1.0% or less in a heating treatment at 120°C for 15 minutes.