Background <p><i>Aedes albopictus</i> mosquitoes and the mosquito-borne diseases (MBDs) they transmit are spreading throughout France. Yet, research on the perceptions and behaviors of the French population regarding MBDs remains scarce and outdated.</p> Aim <p>To quantify the knowledge, attitudes, and practices (KAP) regarding MBDs in the metropolitan French population and examine factors influencing MBD protective behavior.</p> Methods <p>In November 2023, we conducted a cross-sectional KAP survey among a quasi-representative sample (<i>n</i> = 2,087) of adults aged 18 to 79 living in metropolitan France. We used mixed-effects models to examine factors influencing the frequency and variety of protective behavior separately.</p> Results <p>During summer, most participants were bitten by mosquitoes in their daily lives (73%) and engaged in protective behavior a few (39%) or several times per week (41%). Mosquito biting frequency was the most influential determinant of protective behavior. Concern of contracting MBDs (cumulative odds ratio [COR] = 1.16; 95% CI: 1.12, 1.21) and experiencing financial difficulties (COR = 1.25; 95% CI: 1.02, 1.54) were determinants of protective behavior frequency. Participants reported engaging in a higher variety of protective behaviors if they had greater concern of contracting MBDs (incidence rate ratio [IRR] = 1.06; CI: 1.04, 1.08), had a higher MBD knowledge (IRR = 1.06; CI: 1.04, 1.08), and had a chronic disease (IRR = 1.05; CI: 1.02, 1.07).</p> Conclusions <p>Concerns of contracting MBDs and MBD knowledge are modifiable factors that influence the frequency and variety of protective behaviors. KAP studies can inform health campaigns and interventions to prevent MBDs.</p>