The correlations of soil physicochemical parameters with the total content of arsenic(As) and the available content of arsenic were analyzed based on the measured contents of arsenic, total phosphorus, organic matter and soil moisture in soils around a mine in Inner Mongolia area. There were two mixed samples consisting of coal gangue and local natural topsoil. Arsenic was separated out from the mixed samples through leaching process at different pH values according to rainfall amount and characteristics. Results show that there was a significantly positive correlation between the available arsenic and the total arsenic content. Total arsenic content had a certain positive correlation with pH value and total phosphorus, but insignificant correlation with organic matter and hydrolysable nitrogen. The available As content had a positive correlation with organic matter, but a negative correlation with pH value. The arsenic leaching decreased with the increasing pH value of leaching solution. The lower pH value was, the higher arsenic leaching was.