Caulerpa racemosa belongs to a group of green algae commonly called sea grapes. The green color as a characteristic of C. racemosa is closely related to the chlorophyll pigment it contains. The concentration of chlorophyll in algae is influenced by the addition of nutrients to the rearing medium, such as nitrate (N) and phosphate (P) nutrients. To figure out the effect of adding N and P using urea and SP36 fertilizers with different concentrations on the chlorophyll content of C.racemosa was the main target of the current study. The research was conducted indoors, using a completely randomized design (CRD) consisting of 5 treatments and 3 replications. The treatment was a comparison of urea and SP36 as follows: A (100 : 0 %), B (75  25 %), C (50: 50 %), D (25: 75 %),  and E (0: 100 % ). The addition of N and P into the media using urea and SP 36 fertilizers in a ratio (50: 50%) resulted in the highest concentrations of chlorophyll a, chlorophyll b, and total chlorophyll. The lowest chlorophyll was found in treatment E, namely the addition of P without N (Urea 0: SP 36 100 %).