The effectiveness of a mulching material for conserving soil and water is not only dependent upon the material itself, but also controlled by the microclimatic environment that the material is subjected to; especially for bio-degradable materials. Therefore, the objectives of the study are (1). to monitor the soil loss and surface runoff produced from tested mulching materials and (2). to monitor the microclimatic characteristics between mulching materials. A variety of mulching materials was used in this study; including Bahia grass residue, chaff, Japanese silver grass residue, tree branches, and synthetic multi-function filter. Two outdoor experimental sites with the slope steepness of 9% and 60% respectively were used to collect data.Field data indicate that Bahia grass residue and multi-function filter were very effective in soil loss reduction on the 60% slope; whereas, Bahia grass residues, chaff, and Japanese silver grass residue could greatly reduce soil losses on the 9% slope. Because of the weak contact that multi-function filter provided to the soil, under-Tilling problem was found on sites. Bahia grass residue and chaff were the best ones among test materials in conserving moisture.Microclimatical characteristics that test materials created could provide reasonable explanations to moisture conservation. Because of the close contact that it produced, Bahia grass residue had the highest variation of 28.7°C in ground temperature and 18.5°C in air temperature beneath the mulch. On the other hand, chaff had the lowest variation of 8.0°C and 10.0°C in ground and air temperatures beneath the mulch, respectively. Even though chaff has limited capacity withholding moisture, the spaces between chaff grains actually form small air pockets that affect the heat transfer within chaff mulch. In addition, chaff mulch had the greatest Albedo of 30.9%. Hence, the ground and air temperatures beneath the chaff mulch did not vary correspondingly with the temperature above the mulch. With the assistance from air pockets between grains, trapped moisture can not easily get out of the micro-environment. Therefore, chaff mulch had highest relative humidity of 86% among all test materials.