The amelioration of steel slag and rice husk bokashi to Andisols are the effort to improve soil chemical characteristics, particularly in decreasing the high P-retention and increasing the low available P. The comprehensive soil characteristics had to be investigated to conceive the entirely influences of those ameliorants. The objective of this research was to compile the influence of steel slag and rice husk bokashi to several soil chemical, physical and biological characteristics on Andisols. The treatments were arranged in Randomized Block Designed in factorial pattern with two factors: steel slag and rice husk bokashi, each consisted of four level: 0, 2.5, 5.0 and 7.5 % in 10 kg soil weight (w/w), made 16 combined treatments and repeated three times. The treatments were incubated for four months and then be analyzed the soil characteristics. The results showed that steel slag and rice husk bokashi interacted in decreasing 6.67% of P-retention and increasing 60 ppm of available P, however did not interact to CEC and base saturation. Toward the soil physical characteristics, the treatments did not interacted but showed individual influence in decreasing bulk density, and increasing permeability and aggregate stability. To soil biological characteristics, there was neither interaction nor individual influence of steel slag and rice husk bokashi to population of total bacteria and phosphate solubilizing bacteria.