A robust RP-HPLC technique was set up for the estimation of Abiraterone & Niraparib. SST parameters, including resolution, theoretical plates, & tailing factor, were within acceptable boundaries, ensuring the technique's reliability. technique verification followed ICH rules, demonstrating high assay accuracy with recoveries within 98-102%. The linearity scale was 10-50 µg per ml for Abiraterone & 2-10 µg per ml for Niraparib, with R2 of 0.999. Precision, ID precision, & robustness tests confirmed the technique's consistency across different conditions. LOD & LOQ were established, showcasing the technique's sensitivity. This verified RP-HPLC technique is suitable for regular analysis of Abiraterone & Niraparib in l formulations.