Background: Influenza virus (IFV), respiratory syncytial virus (RSV), parainfluenza virus (PIV), and metapneumovirus (MPV) are the most common viruses associated with acute lower respiratory infections in young children and the elderly. A global report of the monthly activity of these viruses is needed to inform public health strategies and programmes for their control. Methods: We conducted a systematic review of population-based studies supplemented by online data and unpublished research data reporting seasonality of IFV, RSV, PIV, and MPV. We calculated monthly annual average percentage (AAP) as the relative strength of virus activity. We defined duration of epidemics as the minimum number of months to account for 75% of annual positive samples, with each component month defined as an epidemic month. Furthermore, we modelled monthly AAP of IFV and RSV using site-specific temperature and relative humidity for the prediction of local average epidemic months. We also predicted global epidemic months of IFV and RSV on a 5° by 5° grid. The dataset contains the global seasonality of influenza virus, respiratory syncytial virus, parainfluenza virus, and human metapneumovirus. The data dictionary can be found in the second sheet of the excel file. R codes can be found in the word file. Funding: European Union Innovative Medicines Initiative: Respiratory Syncytial Virus Consortium in Europe (RESCEU)The dataset contains the global seasonality of influenza virus, respiratory syncytial virus, parainfluenza virus, and human metapneumovirus. The data dictionary can be found in the second sheet of the excel file. R codes can be found in the word file.