1. One of the major factors which effect the yield of the graclaria. agar is theacid concentration at which in the range of 2 .5--4. 0% the product can be prepared.For reinforcing the strength of the products, the acid concentraction would beadjustcdat 2. 0--2.5%, and for increasing the productivity 4. 0--5. 0% would be selecled. Byballancing the reciprocal aid, 3. 5% is selected suitably. 2. The acidification processing operates under the given acid value duration issimple and the data is reliable as well as the good quality of products in copmaring tothe other methods. It would contribute to commercial scale of agar production. 3. In the extracting procoss the bleaching agent is mixes at first with acid andthen the acidification and bleach action take place at same time. Tt is characterised byrapid reaction speed, faster bleaching with lcss bleaching agents. The processing have been adopted by Lanhai Farm's Agar Laboratory Factory inHaikou and a good production with 21. 6% of average yield and 650 g/em~2 of averagestrength of the agar have been achieved.