We evaluated the arbovirus exposure among 185 Papua New Guinea military personnel (PNGMP) before 2023 by an Enzyme-Linked Immunosorbent Assay(ELISA) IgG/M and neutralization assays. Overall, sero-positivity of PNGMP sera were anti-chikungunya virus(CHIKV) IgG 46.5%(86/185), IgM 5.9%(11/185) and neutralizing antibody (Nab) 33.5%(62/185). Anti-dengue (DENV) were IgG 97.8%(182/185) and IgM 13%(24/185). The anti-DENV1-4 monotypic Nab were DENV1 94.1%(174/185), DENV2 93%(172/185), DENV3 95.1%(176/185) and DENV4 31.3%(58/185). Anti-Zika virus(ZIKV) were IgG 71.4%(132/185), IgM 4.3%(8/185) and Nab 87%(161/185); Anti-Ross River virus(RRV) were IgG 41.6%(86/185), IgM 9.7%(18/185) and Nab 44.3%(82/185). Anti-Barmah Forest virus (BFV) were IgG 10.3%(19/185), IgM 7.0%(13/185) and NAb 10.8%(20/185). Anti-Japanese encephalitis virus(JEV) Nab was 62%(115/185) Anti-West Nile virus(WNV) was Nab 19.5%(36/185) and Anti-Murray Valley encephalitis virus(MVEV) Nab was 39.4%(73/185). There is no significant difference between age groups in sero-prevalence for all viruses. Among the participants, 31.9% were IgG and 34.6%(64/185) Nab positive for all anti-DENV, anti-CHIKV and anti-ZIKV . The high percentage of IgM+ results suggested that PNGMP are frequently exposed to arbovirus as IgM antibodies typically wane within 3 months after infection. Our findings indicate that the majority of PNGMP have been exposed to DENV and ZIKV, with some exposure to CHIKV, RRV, JEV and MVEV and less to BFV and WNV. The sensitivity for ELISA-IgG ranged from 78%-89% and the specificity 74% to 100% calculated using Nab results as reference. Our small number of serum infected with a single RRV, DENV and CHIKV virus results indicated that broad cross reactivity among flavivirus and alphavirus genus in ELISA assays, suggesting that it might not be suitable for surveillance purposes in multiple arbovirus endemic areas such as PNG. Our study highlights the circulation of multiple mosquito-borne viruses in PNG. Therefore it is important for Australian Defence Force personnel traveling to PNG to take preventive measures in order to minimize mosquito bites.