An elastic ferromagnetic composite with a conducting matrix is described. The composite consists of silicon steel particles of size 150-200 μm and graphite particles of size not exceeding 0.5 μm dispersed in polymerized silicone. The resistivity of the composite amounted to (8.32-0.28)x10 - 3 Ω m and depended on its chemical constitution. The structure of the system with a variable capacitance capacitor for a simultaneous measurement of magnetostriction and magnetoresistance of the produced composite is also described. The measurements were carried out in a magnetic field with induction amounting to 0-8 T generated by a Bitter type magnet. It was found that in a field with induction of 8 T the composite exhibits, depending on its chemical composition, longitudinal magnetostriction (0.14-0.80)x10 - 2 and relative longitudinal magnetoresistance 21.5-37.5%. After switching off the field, a hysteresis of magnetostriction of (0.03-0.13)x10 - 2 and a hysteresis of magnetoresistance of 6-14% was observed.