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The coconut hispine beetle, Brontispa longissima Gestro, is an invasive and economically important pest of palm trees in China. Beauveria bassiana has been used widely to control agriculture and forestry pests, for example, Dendrolimus punctatus Walker, Pantana phyllostachysae Chao, and Basilepta melanopus Lefevre. Until now, there is no published data on the use of B. bassiana against B. longissima. In this study, we identified highly pathogenic B. bassiana strains against different developmental stages of B. longissima under laboratory conditions. The BB-01 strain presented the highest virulence against B. longissima. After inoculating with the BB-01 strain at (1.0 ± 0.5) × 107 spores·mL−1for 10 d (28 ± 1°C with 95 ± 1% relative humidity), the corrected mortality of B. longissima adults reached 94.7% with a LT50 of 5.3 days. Mortality on other developmental stages was 84.4 ± 3.3% (LT50 = 5.8 d) for 1st-2nd instars, 76.1 ± 1.2% (LT50 = 6.71 d) for 3rd-4th instars, 73.7 ± 1.1% (LT50 = 6.98 d) for ≥5 instars, respectively. BB-01 median lethal concentrations (LC50) against 1st-2nd instar, 3rd-4th instar, ≥5 instar larvae and adults for 6 d were 9.0 × 106, 3.5 × 107, 4.8 × 107, 9.1 × 105 spores·mL−1, respectively. The BB-01 strain exhibited a lethal effect peak on B. longissima at 6–7 d after treatment. This study provides basic data about the pathogenicity of different B. bassiana strains on B. longissima. [ABSTRACT FROM AUTHOR]