Physical properties up to 600 K are studied for (TMTSF)(2)PF6, (TMTTF)(2)PF6, (DMET)(2)I-3, (DMET)(2)AuI2, (DIMET)(2)I-3, (DIMET)(2)AuI2 and kappa-(ET)(2)Cu(NCS)(2). It has been found that all the compounds decompose between 450 and 500 K by TG-DTA measurement. Electric resistivity and thermopower of the TMTSF and DMET salts are metallic as were expected from their temperature dependence below 300 K The TMTTF and DIMET salts show constant thermopower, though their resistivity is metallic. This suggests that Me TMTTFand DIMET salts are intrinsically non-metallic even above room temperature. Rapid decrease in resistivity found for many of the Q1D salts before their decomposition suggests the partial escape of anions and change in the carrier concentration. kappa-(BEDT-TTF)(2)Cu(NCS)(2) shows hysteretic temperature dependence of the resistivity above 300 K.