Background and Objectives: Camel breeding is one of the sources of income for people on the edge of arid and desert regions across various parts of the world. Traits associated with camel growth, including birth weight, weaning weight, daily weight gain, and oneyear-old weight, are considered as the principal economic attributes for camel owners. To manage and enhance the genetic and phenotypic values of these traits, animal weight recording is imperative. Recording the weight of camels, particularly due to their restless temperament and substantial size, presents numerous challenges. The utilization of effective mathematical methodologies can substantially mitigate this issue. Various approved efficient mathematical methods have been proposed to predict the weight of camels based on their body dimension, and their efficacy has been proven. Therefore, the present study was conducted to compare the effectiveness of principal component analysis and multiple regression in estimating the weight of fattening camels based on their body dimensions. Materials and Methods: In order to compare the efficiency of principal components analysis and multiple regression in estimating the weight of fattening camels based on body dimensions, the records of 220 fattening camels at the Bafgh station in Yazd were used. For this purpose, newborn camels were fed for a 9-month period using standard diets. During the period, each of the fattening camels was weighed and different body sizes including body length (BL), whither height (WH), breast girth (BG), abdomen width (AW), hump height to the ground (HH), muzzle girth (MG), neck length (NEL), whither to pin length (WPL), tail length (TL), pelvic width (PW), abdomen to hump height (ABH) and the head length (HL) were measured. The body dimensions of the camels were recorded using a tape measure, and their body weight was measured using a scale. Subsequently, the data were analyzed using the principal component analysis and multiple regression methods. In order to fit the predictive models, the body weight of camels was introduced as the dependent variable, and the body size of camels was introduced as the independent variable. The analysis of regression models was performed using both one-variable and multivariable linear models, and the best models were selected to estimate the weight of camels based on their body dimensions through the stepwise method. The performance of the above models was evaluated by comparing their coefficients of determination (R2). Results: According to the results, the correlations between the body weight of camels and their different body dimensions, including BL, WH, BG, AW, HH, MG, NEL, WPL, TL, PW,ABH, and HL, were 0.93, 0.89, 0.89, 0.89, 0.94, 0.73, 0.89, 0.90, 0.80, 0.85, 0.89, and 0.79, respectively. The results showed that, among the six multiple regression models fitted to estimate the weight of fattening camels, model No. 6 - utilizing head length, body length, breast girth, neck length, muzzle girth, and whither height as predictive variables - had the lowest error (12.06) and the highest accuracy (0.92) compared to the other models. Additionally, the results showed that utilizing the first and second principal components, along with both of them in the model, could explain 82.1%, 3.73% and 85% of the variance in body weight, respectively. The weight of fattening camels was determined using principal component analysis with an accuracy of 0.93 and an error of 11.54. Conclusion: The results of the present study showed that in order to estimate the weight of fattening camels, the use of principal component analysis, in addition to simplifying predictive models, has higher efficiency and accuracy as well as less error compared to multiple regression, and this method can be a suitable alternative to the multiple regression method in predicting the weight of camels. [ABSTRACT FROM AUTHOR]