This study was performed to evaluate the production and titer of anti-D serum from individuals with negative rhesus factor for determining rhesus blood group. Anti-D serum obtained have the some titer as anti-D from the control Indonesian Red Cross, viz 1/32 but with higher average avidity at p less than or equal to 0.01 equal to 57 seconds. This anti-D serum gives spesific reaction against pos…