The concentrations and pollution characteristics of metal elements in fine particulate matter (PM2.5) during haze-fog days in winter in the urban area of Beijing were investigated. Aerosol samples of PM2.5 were collected in Beijing for 23 consecutive days from January to February, 2013. The concentrations of PM2.5 were measured by filter membrane weighting method. The samples were treated by ultrasound exacting procedures and the total amounts of the 36 metal elements were determined by inductively couple plasma-mass spectrometry (ICP-MS). The pollution characteristics of metal elements were analyzed by enrichment factor (EFs) method. The concentrations of PM2.5 significantly increased in haze-fog days, which were much higher than the 24 h mean value (75 μg·m-3) in National Ambient Air Quality Standard issued by Ministry of Environmental Protection of the People’s Republic of China. Among the 36 metal elements, the concentrations of 27 metal elements in PM2.5 were higher in haze-fog days than those in normal days. As, Cr, Pb, Ti and V were the principal inorganic components of PM2.5 in winter in the urban area of Beijing. In haze-fog days, the metal elements could be roughly divided into 3 groups by EFs, including high-enrichment group (EFs were higher than 10, including As, Cr, Cu, and Pb), medium-enrichment group (EFs were between 10 to 1, including Sb, Sn, etc) and low-enrichment group (EFs were close to 1, including Ti, V, etc). It was concluded that ICP-MS has good precision and accuracy in determining multi elements in atmospheric particulate samples, and can meet the requirements of monitoring principal and trace elements of pollutants simultaneously. In haze-fog days, the increase of As, Cr, Pb were strongly correlated with the pollutions caused by anthropogenic activities, such as vehicle exhaust emissions, and oil and coal combustions in winter. This study can probably provide a useful analytical method for the elements characteristic detection of PM2.5 in haze-fog days, and provide scientific basis for decreasing air pollution in Beijing and protecting the people’s health.