During the period trom February-April of 2013, the authors conducted experiments on producing organic fertilizers tro agricultural by-products in Quang Yen district, Cao Bang province. The results showed that compostion of mixture (com stalks, rice straw) with the preparations, the temperature in the composted bucket increased during composting progress. By day 12, the temperature in buckets reached the peak, then decreased gradually, and together with the temperature fall, the weight and volume of the composted buckets fell down as well. Results of using compost fertilizers after planting vegetable indicated that vegetable applied fertilizers composted by mixture of com stalks, rice straw with the EM, ash and alcoholic ferment developed better, its height and number of leave and productivity were higher than non-composted fertilizers.