An installation for treating biological liquid by chromatography, generally extending in a longitudinal direction and comprising: - at least one supply valve for supplying biological liquid to treat, configured to be connected to at least one biological liquid supply container; - at least one supply pump disposed downstream of said at least one supply valve and connected to the latter; - a plurality of instrument members disposed downstream of said at least one supply pump, including distribution valves (81a-c, 82a-c, 83a-c) and devices (78a-c, 85a-c, 86a-c) for measuring physico-chemical parameters of the biological liquid, and which are connected to said at least one supply pump; - a plurality of chromatography columns (99a-c) disposed downstream of said plurality of instrument members, each of said chromatography columns being directly associated with and connected to at least some of said instrument members, and being configured to be supplied with biological liquid by said at least one supply pump; and - a plurality of single-use pipes configured to be connected to said at least one supply valve, to said at least one supply pump, to said plurality of instrument members and to said plurality of chromatography columns, so as to form at least one supply line for supplying biological liquid to treat of a treatment circuit of said installation; characterized in that said chromatography columns are disposed (99a-c) relative to each other in a direction of extension generally transverse to said generally longitudinal direction of extension of said installation; and in that some of said instrument members associated with said chromatography columns (99a-c) are mounted on dedicated control and actuation platforms (80a-c) which are disposed in the same general transverse direction as said chromatography columns and which are substantially above said respective chromatography columns. - at least one supply valve for supplying biological liquid to treat, configured to be connected to at least one biological liquid supply container; - at least one supply pump disposed downstream of said at least one supply valve and connected to the latter; - a plurality of instrument members disposed downstream of said at least one supply pump, including distribution valves (81a-c, 82a-c, 83a-c) and devices (78a-c, 85a-c, 86a-c) for measuring physico-chemical parameters of the biological liquid, and which are connected to said at least one supply pump; - a plurality of chromatography columns (99a-c) disposed downstream of said plurality of instrument members, each of said chromatography columns being directly associated with and connected to at least some of said instrument members, and being configured to be supplied with biological liquid by said at least one supply pump; and - a plurality of single-use pipes configured to be connected to said at least one supply valve, to said at least one supply pump, to said plurality of instrument members and to said plurality of chromatography columns, so as to form at least one supply line for supplying biological liquid to treat of a treatment circuit of said installation; characterized in that said chromatography columns are disposed (99a-c) relative to each other in a direction of extension generally transverse to said generally longitudinal direction of extension of said installation; and in that some of said instrument members associated with said chromatography columns (99a-c) are mounted on dedicated control and actuation platforms (80a-c) which are disposed in the same general transverse direction as said chromatography columns and which are substantially above said respective chromatography columns.