A sensing and control apparatus for a battery management system is provided. The sensing and control apparatus includes: a sensing unit and a main control unit. The sensing unit includes: a cell relay of a plurality of cell relays and a voltage detection unit. The cell relay is configured to be coupled to at least one of a plurality of cells. The voltage detection unit is coupled to a cell relay. The voltage detection unit is configured to: receive a reference voltage when each of the plurality of cell relays is turned off; and generate a second voltage by amplifying by a gain a first voltage that corresponds to the reference voltage. The main control unit is configured to calculate a valid gain corresponding to a ratio of the second voltage to the reference voltage when the temperature of the voltage detection unit is within a threshold temperature range.