The disclosure relates to a method and apparatus for real-time transmission in a field broadband bus architecture over an industrial internet, where the field broadband bus architecture over an industrial internet includes: a bus controller, at least one bus terminal, and a two-wire bus over which the bus controller and the bus terminal are connect to constitute a network, the bus controller communicates with any one bus terminal, and the respective bus terminals communicate with each other, using the OFDM technology, and sub-carriers occupied by the respective bus terminals do not interfere with each other; and the method includes: the bus controller receives a fixed-rate service transmitted by the bus terminal in an uplink subframe over pre-allocated fixed-rate service resource blocks; and allocates resource blocks for a variable-rate service of the bus terminal in a real-time manner among variable-rate service resource blocks.