The　medium　temperature　pyrolysis　process　using　a　fixed-bed　reactor　at　atmospheric　pressure　was　utilised　to　recover　carbon　black　from　motorcycle　and　automobile　tyres.　Experimental　results　have　shown　that　the　ash　and　volatile　contents　of　several　recovered　carbon　blacks　are　high,　the　elongation　at　break　of　the　vulcanised　natural　rubber　filled　with　recovered　carbon　blacks　from　motorcycle　tyres　is　better　than　that　from　motorcycle　tyres　and　standard　carbon　black　7#,　while　the　other　mechanical　properties　are　worse.　In　order　to　improve　the　reinforcing　effect　of　recovered　carbon　blacks,　the　modification　of　recovered　carbon　black　was　performed　by　high-energy　electron　bombardment　and　non-oxidising　acid.　The　specific　surface　area　of　the　pyrolytic　carbon　blacks　increased　after　high-energy　electron　bombardment.　The　ash　content　of　the　pyrolytic　carbon　black　was　reduced　from　22.5%　to　8.4%　after　rinsing　with　hydrochloric　acid,　and　the　tensile　stress　at　300%　was　increased　by　about　2.2　MPa.