A method and apparatus for receiving system information from a Base Station (BS) in a Mobile Station (MS) in a mobile communication system are provided, in which it is determined whether there is buffered system information in a buffer, if current system information has an error, it is determined whether a combining condition is satisfied, in the presence of the buffered system information, the combining condition being defined by at least one of a Master Information Block (MIB) value tag, a System Information Block (SIB) value tag, and modification time information that are associated with the current system information, and the current system information is combined with the buffered system information, if the combining condition is satisfied.