Rubber is considered a crop with high potential for some Northwest provinces to improve crop production systems. Results of experiments conducted in 2010 show that there are short duration crop varieties appropriate for intercropping in newly established rubber plantations, and that intercropping system of maize (Spring-Summer) - Legumes (Autumn-Winter) brought a profit of 25,660,000 - 42,680,000 VND/ha/year, the system of legumes (Spring) - upland rice (Summer-Autumn) 24,176,000 - 39,194,000 VND/ha/year. Moreover, these intercropping systems reduced the amount of soil washed off away with 52 percent - 77 percent, and had good impact on rubber tree. The diameter of rubber trees in the experimental plots was 4.5 - 9.3 percent bigger than that in the control plot.