The work investigates applicability of the magnetic hysteresis and Barkhausen noise techniques for testing of ductile cast iron microstructure. The measurements were performed on 4 series of different matrix structures with 5 samples in each series of different size of spheroidal graphite. The samples were magnetized by a single yoke at quasi-static regime; their magnetic field was determined by a 3-point extrapolation of the measured surface field profile to the sample faces. The Barkhausen noise was measured by a perpendicularly attached pancake coil with a laminated soft ferromagnetic core. The magnetic measurements showed a unique correspondence with the hardness, which is commonly used for the matrix structure testing. However, the magnetic response to the graphite morphology revealed lower sensitivity than to the matrix variations. The ultrasonic velocity measurement, which is a usual routine for the graphite structure testing, gave similar but even less sensitive dependencies.