•The fractal growth of chromium dendrites in electrodeposition was studied.•The DLA simulation results are consistent with the actual experimental results.•Dendrite morphology is closely related to particle motion.•The dendritic clusters are primarily composed of three-dimensional grains. This investigated the fractal growth behavior of dendrites during the electrodeposition of chromium metal within two-dimensional confined interface. The effect of influencing factors (voltage, electrolyte concentration, catalyst concentration, and deposition time) on the morphology and fractal dimension of the deposited dendrites was investigated using zero-dimensional point electrodes and one-dimensional wire electrodes. The results indicate that as the voltage and electrolyte concentration increase, the fractal dimension of the point electrode decreases, while that of the wire electrode increases. Additionally, increasing the concentration of the catalyst and the deposition time led to an increase in the fractal dimension for both the point electrode and the wire electrode. This is due to the morphology of the dendritic clusters growing more open or denser depending on the aggregation mode of particles under different experimental conditions. This further leads to changes in fractal dimension. A diffusion-limited aggregation (DLA) model was developed to simulate the motion of particles during deposition. The model demonstrates that the changes in fractal dimension and the morphology of the aggregates formed by particles moving randomly are consistent with the experimental results. Finally, the distribution of grains on the sediment surface revealing that fractal dendrite clusters in a two-dimensional sediment interface consist of three-dimensional grains.