Objective: This study aimed to realizing the three-dimensional visual simulation of the morphological structure of tomatoes. Methods: A new tomato shape equation was derived, which took the radius as a function and included size parameters and shape description coefficients. By calculating the geometric model description coefficients (a, b, c₁, c₂) based on the measured values of the main size parameters of the tomatoes, a three-dimensional geometric model of tomatoes was developed and established their correlation with the weight and height of the tomatoes. Moreover, the accuracy of the model was verified by comparing the measured and predicted values of weight and surface area. Results: The three-dimensional geometric model of tomatoes established based on the size parameters and shape description coefficients could accurately and intuitively describe the local indentation characteristics of the stem ends of tomatoes. The ranges of shape description coefficients a, b, c₁, and c₂ were 21.78~28.58, 30.50~34.54, 0.19~0.53 and 0.04~0.31 mm, respectively, applicability of the model. The study found that coefficients a and b had a high linear correlation with the height and weight of tomatoes (R²＞0.85), indicating that the equation could capture important shape characteristics of tomatoes through simple measurements. The relative percentage error (E_RPE) between the measured values and the model predicted values of weight and surface area was 5.46% and 10.24%, and R² was 0.85 and 0.81, which indicated that the established equations and models could be used to quantify the geometric properties of tomatoes such as weight and surface area. Conclusion: The three-dimensional geometric modeling method of tomatoes proposed in this paper could intuitively, quickly and accurately represent the geometric shape of tomatoes and had strong applicability and exemplary performance in tomato-related computer-aided design and simulation.