The Carbon/Carbon composites, due to possessing a high resistance to thermal shock and excellent mechanical properties such as significant strength and toughness, have been of great interest in the aerospace industry. In this regard, the CVI method is one of the most important methods to produce the C/C composites; however, this method has some disadvantages such as the low growth rate of the carbon over the carbon felt. So, this work was aimed at increasing the growth rate of the CVI method in producing the CF/C composites through using the nickel catalyst. Herein, the carbon felt made of the activated carbon was used as the substrate, over which, the nickel particles were loaded; the nickel nitrate was exploited by dissolving different contents of nickel nitrate in two solvents of acetone and ethanol followed by using ultrasonication and rotary evaporator. Choosing a suitable solvent was done along with optimizing the content of the nickel catalyst over the carbon felt. The appropriate conditions of calcining the nickel nitrate over the carbon felt were determined and afterwards the nickel oxide was reduced under the hydrogen gas. Then, two temperatures of 700­°C and 1050°C were considered to carry out the CVI process at different times. The prepared samples were characterized in terms of the phases, chemical composition, and microstructure via XRD, Raman spectroscopy, ICP, EDS, SEM, FESEM, TEM and HRTEM methods and the specific surface area was determined by the BET Test. Density was obtained by the Archimedes method, mechanical properties were investigated through the Bending Test, and the chemical and thermal stabilities were studied by the TG-DTA analysis. The most important results based on the wettability and the low evaporation temperature of acetone, indicated that the acetone can provide a good distribution and increase the deposition of the nickel to up to 40%. Using the rotary evaporator device not only improved the distribution of the nickelarticles, butalso reduced the size of them after CVI process at 700°C to less than 30 nm. The results corresponding to the CVI process at 700°C in 120 to 1080 min revealed that the deposited carbon was of the MWCNT, where, increasing the process duration raised the nanotubes length significantly, however, their diameter was constant in the range of 20-30 nm. In addition, by increasing the amount of the nickel catalyst particles, the amount of the MWCNT tubes was raised substantially. For example, by increasing the process duration for the sample containing 40 wt% nickel particles, the density of the sample was increased from 0.3 g/cm -3 to 0.67 g/cm -3 , in contrast, the specific surface area was reduced from 200 to 51 m 2 /g due to the entanglement of the MWCNTs. From the obtained results, it can be deduced that the CF/MWCNT composite has been formed by the CVI process at 700 °C. Therefore, to proceed the research, the sample prepared after 1080 min by the CVI process at 700 °C was considered. The results of the CVI process at 1050 °C for 720 min declared that the density was increased from 0.67 g/cm -3 to 1.73g/cm -3 . In addition, this can also be argued from HRTEM microscope images that the majority of the entanglement inner filaments of the MWCNTs remained intact and only the surface portion of the fibers was damaged because of the nucleation and growth of the pyrolytic carbon. As a result, this can be introduced as a CF/MWCNT/PyC three-component composite. Furthermore, it was found that the formation of the MWCCNT fibers at 700 °C can decrease 84% of the whole time of producing CF/C composite through the CVI process at 1050 °C. Keywords : Carbon Felt; Nickel catalyst; CVI proce MWCNTs; CF /MWCNT composite; Pyrolytic carbo Composite CF /MWCNT/ PyC