The laboratory bioassays showed the frozen stored Rhynchophorus polyhedrosis virus (FSRPV) and newly extracted one from died red palm weevil, Rhychophorus ferrugineus (oliv.) (RPW) collected from the field. The FSRPV was stored for 18 months under -4oC. The newly extracted Rhynchophorus polyhedrosis virus (NERPV) was used for contamination of laboratory reared larvae of RPW at different ages in comparison of the pathogenicity between FSRPV and NERPV. The infected larvae were bioassayed and LC₅₀ and LT₅₀ values were determined. The range of LC₅₀ for NERPV was from 2.6x10⁷ to 4.0x10⁷ Polyhedra Inclusion Bodies (PIBs) /100 g diet, while the LC₅₀ for FSRPV ranged between 3.3 to 3.8x10⁷ PIBs/100 g diet. The range of LT₅₀ for NERPV was from 2.4 to 24.3 days while it was from 3.2 to 25.9 days for FSRPS.