Abstarct: The 252Cf source is a spontaneous fission source that emits gamma rays, alpha and beta particles, in addition to neutrons. The main aim of radiotherapy is to eliminate malignant tumors with minimal damage to surrounding healthy tissues. Neutron and gamma rays, due to their high penetration depth in tissue Possibility have to deposit some of their energy around the tumor. To achieve the desired results, to reduce the damage caused by these radiations in healthy tissues and increase the dose in the tumor, 10B and 157Gd nuclei can be used due to the high absorption neutron cross-section and 197Au nanoparticles due to the absorption of gamma rays. In this study, by using MCNPX.2.6.0 Monte Carlo code dosimetry parameters of the 252Cf source in neutron brachytherapy calculated according to the TG-43U1 protocol. The absorbed dose rate of all effective rays obtained in dosimetry around the source in water media and soft tissue at different distances. Moreover, the possibility was examined the beta particles escape and X-rays produced during the pass of the source capsule. The results showed that the relative difference in the calculation of the dose rate caused by bremsstrahlung x-rays and beta particles in the total equivalent dose versus ignoring these rays, at the 0.50 cm distance of the source % 19 and the 0.75 and 1.00 cm distances is more than % 14 and % 9 respectively. As the distance from the source increases, the effect of these radiations on the total equivalent dose decreases. However, in the 2.50 cm distance, its values are less than 0.5 %. By investigating the effect of different concentrations of 10B and 157Gd particles and nanoparticles to increase the absorption dose of neutrons in equal concentrations of boron and gadolinium observed that, the total equivalent dose rate of boron is more than gadolinium. The relative difference of the total equivalent dose rate with the 50 ppm boron in the tumor versus its absence in the tumor increases with increasing distance from the source. Therefore, from 24 % at the distance of 5.1 cm approximately achieving to 31 % at the distance of 5.9 cm. Furthermore, in the comparisons of the total equivalent dose rate with the presence of particles and nanoparticles of boron and gadolinium in the tumor with each other, no significant change was observed in increasing the total equivalent dose rate. Also, the effect of different concentrations 197Au particles and nanoparticles was evaluating on the gamma dose absorbed. The relative difference of total gamma dose with the presence of the 30 mg/g of gold particles in the soft tissue compared to the absence of gold in the soft tissue, in this case, showed approx 27 %. For further research, the gamma emitter source 192Ir was using, in the simulations. Using iridium source, however, the relative difference of gamma dose with the presence of 30 mg/g of the gold particles in the soft tissue as, compared to the absence of gold in the soft tissue, was obtained % 40 approximately. Therefore by comparing the results of the two sources was observed that the rate of increase in gamma dose with the presence of the gold particles and nanoparticles depend on the source energy spectrum and the type of interactions with the matter. Using the whole-body phantom of the female and considering the different stages of cervix cancer progression, the source was placed at the site of the tumor and the equivalent dose rate of radiations in the other organs was also calculated. To increase the neutrons absorption rate in the tumor caused by the cervix in the second stage of the disease progression stages, 50 ppm boron in the tumor was considering and, in this case, was obtained total the equivalent dose rate. However, the results showed that the addition of boron in the tumor had little effect on increasing the neutrons absorption dose on it and reducing theirs effects on the surrounding healthy organs. The relative difference is only % 5 proximally. Finally, considering the fourth stage of cervical cancer progression, in which the disease affects some adjacent organs in addition to the uterus, for a bladder tumor that is further away from the source, the total dose rate with 50 ppm Boron and the without of boron, was obtained in the bladder. The relative difference between the usage and the absence of boron was obtained for the bladder and its contents about %38 and %22, respectively.