Non-treated and silane-treated kenaf bast/natural rubber latex foam (NRLF) were prepared using the Dunlop method at different filler loading (0, 3, 5, and 7 pphr). The properties were investigated in terms of mechanical properties, tensile, compression, hardness, and swelling behavior. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to characterize kenaf bast/NRLF. With the modulus at 100% elongation (M100), the compression strength and hardness showed increments in value with increments of kenaf loading. However, different results showed in tensile strength, elongation at break, swelling percentage, and recovery percentage, which decreased at higher filler loading. Silane-treated kenaf bast/NRLF showed higher value in all properties except for elongation at break, swelling, and recovery percentage. The improvement of properties was supported by SEM surface morphological studies that showed better adhesion between the rubber matrix and kenaf filler.