The invention discloses an on-line number of people distribution calculation method and device, and belongs to the field of on-line live broadcast. The method includes the steps: obtaining on-line time periods of each user corresponding to different types of client sides in an Internet product; for the on-line time periods of each user corresponding to different types of clients which intersect, splitting according to intersection endpoints to obtain split time periods of each user under different on-line types; and according to the split time periods of each user under different on-line types, calculating on-line number of people statistical data corresponding to a certain type of clients. The method solves the problems that when on-line number of people statistical data corresponding to different types of clients are calculated, the calculation quantity is enormous, and calculation is time-consuming; and the effects of avoiding a Cartesian product and a large amount of duplicate removing calculation in a calculation process, simplifying data when distribution situations of the on-line number of people on different types of client is calculated, reducing the calculated amount of calculation data, and improving algorithm operation efficiency are achieved.