This community service activity in KarangIntanDistrictwas aimed to (1) provide technical guidanceabout simple technology and counseling about the use of sawdust and rice husk in cultivating oyster mushrooms; (2) inform the technology of oyster mushrooms cultivation as one of business diversification; and (3) empower the people to develop oyster mushrooms cultivation by using local resources of sawdust and rice husk. This activity includes introduction and technical guidance of oyster mushroom by using sawdust and rice husk, which involved 20 citizens of Mandiangin Barat Dalam Village, KarangIntan District, Banjar Regency, South Kalimantan. The activity was started from lecture activities (counseling) about the use of sawdust and rice husk in cultivating oyster mushroom. The further field activities include the demonstration of making ―kumbung‖ to house the cultivation of oyster mushroom, the preparation of growth medium, the making of bag log, upkeep, and harvesting. Based on the early evaluation about the knowledge they have it can be concluded that their knowledge on the use of sawdust and rice husk in cultivating oyster mushroom was very low. Most of them only heard about it, without further knowledge. This can be seen from average score per respondent per question at early evaluation (0,322), but after evaluation the score went up to 3,156. The people gave their positive responses to learn about marketing the product and their eagerness to find out about the more profitable end result to earn extra income. The abundance of unused rice husk is also a potential for further development. Key words: sawdust, rice husk, oyster mushroom