IN THE PRODUCTION OF VANADIUM OXYTRICHLORIDE WHEREIN VANADIUM PENTOXID, CARBON AND CHLORINE ARE REACTED, THE IMPROVEMENT WHICH COMPRISES EFFECTING THE REACTION BY CONTACTING A MIXTURE OF FINE-GRAINED VANADIUM PENTOXIDE AND CARBON IN THE FORM OF A GAS PERMEABLE LAYER ABOUT 0.5 TO 20 CM. HIGH WITH CHLORINE AT A TEMPERATURE OF ABOUT 350 TO 750*C. PREFERABLY THE PROCESS IS CARRIED OUT CONTINUOUSLY AND THE REACTION TEMPERATURE IS MAINTAINED AND CONTROLLED BY REGULATING THE RATE OF ADDITION OF THE REACTANTS. THE RESULTING VANADIUM OXYTRICHLORIDE IS VOLATILIZED AT A TEMPERATURE OF ABOUT 150*C. AND IS THEREAFTER CONDENSED.