Guinea, like many other African countries, has been facing an unprecedented COVID-19 outbreak, since March 2020. In April 2020, Guinean National agency for health security recorded 1351 confirmed cases of COVID-19, including 313 recoveries and 07 deaths. To address this health crisis, some drastic measures were implemented to prevent the spread of COVID-19. Those measures might potentially cause some psychological problems among Guineans. Thus, we conducted this study to assess the psychosocial impacts of COVID-19 in the Guinean population. We carried out an online cross-sectional survey among internet users in Guinea. A free e-survey platform was used, and questionnaires were sent to internet users. The study ran from May 1 through May 10 2020. Participation in the study was voluntary. Data collection was based on sociodemographic information and self-reported questionnaires: Impact of Event Scale-Revised (IES-R) for stress evaluation, Penn state worry questionnaire (PSWQ), and an adapted Social Psychological Measurements of COVID-19. A total of 280 participants took part in the study; responses from 5 participants were deleted because of incompleteness. The average age of participants was 28.9 [95% CI: 28.1;29.6]. Most of participants were male 65.5% [95% CI: 59.5%;71.1%]. Unemployed participants stood for 48.7% [95% CI: 42.7%;54.8%]. IES-R scale for stress evaluation yielded the following findings: 19.6% (mild), 5.23% (moderate) and 9.15% (severe); 82.8% and 17.2% of participants had respectively reported low and moderate worry. No significant statistical association was found between sociodemographic variables and traumatic events (IES-R and PSWQ). However, 82% of our participants had to cope with the negative impacts of COVID-19. Although there were few cases of traumatic events, negative impacts of COVID-19 on study participants deserve to be underlined. So, further investigations are necessary to identify and disentangle specific psychosocial problems in different Guinean socio-cultural contexts.