Small and large natural rubber particles were prepared by centrifugation. After that, the latexes were dried and mixed with carbon black to obtain compound samples. The interaction between rubber matrix and carbon black and the influence of storage time were studied. It is shown that the rubber compound obtained from small rubber particles has a higher bound rubber content. As the storage time prolonging, the bound rubber content of samples with small rubber particles increases at first and decreases at last while that of sample obtained from large rubber particles keeps rising. The results of scanning electron microscopy show that the dispersion of carbon black and compatibility between carbon black and rubber matrix in the samples prepared by small rubber particle latex is poor, with lots of trapped rubber existing. While the dispersity of carbon black in the samples prepared by large rubber particle latex is better. The glass transition characteristics of bound rubber samples measured by differential scanning calorimeter shows that the difference value of specific heat flow before and after glass transition of the bound samples increases firstly and then decreases with the prolonging of storage time, because the continuous rubber phase increases firstly and then decreases. In a word, the measured bound rubber content of natural rubber prepared from small rubber particle latex is higher, but the compatibility with carbon black of that is poor, and most of them are trapped rubber limited in filler particles.