The paper presents the results of the study on sintering of the AlB12C2 submicron powder and synthesis of AlB12C2-based ceramics from the submicron α-AlB12 powder with C and TiC additions by hot pressing at 30 MPa. The material sintered at 1950°C from AlB12C2 which contained about 100% of AlB12C2 according to the X-ray analysis, demonstrated the density p=2.57 g/cm3, fracture toughness K1c(49 N)=3.4 MPa·m0.5, hardness Hv(49N)=27.9 GPa, bending strength Rbs=311 MPa and compression strength Rcs=1461 MPa; while the SEM study showed that the material consisted of two phases with approximate stoichiometrics: Ala15B11C2 (matrix phase) and Al2O3.5B1.1 (inclusions). The material synthesized at 1950°C from α-AlB12 with 20% TiC contained 74% AlB12C2, 22% TiB2, 4% Al2O3 according to the X-ray analysis and showed Hv(49N)=28.9 GPa, K1c(49 N)=5.2 MPa·m0.3, Rbs=633 MPa and Rcs=640 MPa, but its density was higher, p=3.2 g/cm3. Additions of 17% C to the α-AlB12 powder lead to 86% AlB12C2 and 14% A1N composition with p=2.7 g/cm3, K1c(49 N) = 5.9 MPa·m0.5, Rcs, = 423 MPa. Rbs=310 MPa. Materials sintered for comparison from α-AIlB12 at 30 MPa, 2O8O-1950°C turned out to be 94-98% α-AlB12 (p=2.58 g/cm3) and demonstrated Hv(49N)=24.1 GPa, K1c(49 N)=4.9 MPa·m0.5, Rbs=336 MPa and Rcs=378 MPa.