Research of Growth Rate of Gracilaria sp. by Multilevel Racks Method at Kalianda Waters, South Lampung was held at May until June 2010. The aim of this research were to know and analyze comparative growth of Gracilaria sp. by multilevel racks method consisting of 5 levels with different depth of each level, through measurement : average of weight gain, growth rate, and growth relative. Data was analyzed by using ANOVA (Tukey test) to assess whether the average of the five levels statistically different each other. The highest Gracilaria sp. comparative growth in 6 weeks period on research was available at first level with 30,2 gr/week. The highest growth rate was available at first level with 4,25 %gr/day. The highest growth relative was available at first level with 1,86 gr. The result of research showed that level 1 and level 2 (depth of 30 cm and 60 cm) was the effective growth rate level than the others.