The pond cultivation of Gracilaria fisheri was conducted at three provinces in the south of Thailand. The samples included seaweed water and sediment were collected at four ponds in each province for the analysis. The parameters of light intensity, salinity, pH, water depth and transparency were directly measured at the ponds. Agar yield and contaminants of the seaweed were measured. Pigment constituents and some elements in seaweed, water and sediment were determined. A highest yield of the seaweed was more than 58 ton ha-1 year-1 fw. The yield was related inverse strongly to salinity, nitrate-nitrogen ion, and epiphyte. The pigment positive related with clay in water. The agar was positive dependent to manganese ion in water. For major elements, the concentration of K and Na in seaweed showed the relation with the concentration of Mg, Zn, N, P in water. Trace elements in seaweed were mainly dependent on some parameters in soil and few parameters in water. The controlling of salinity and adding of fertilizer in water could be improve algal biomass and