A method for performing in a modular arithmetic coprocessor an integer division of a first binary data element by a second binary data element. The result is obtained by making an iterative loop of operations including an integer division of the first data element by a most significant word of the second data element. A test is performed to determine if the result of the division performed corresponds to a word of the final result sought. The first data element is modified by subtracting from it a data element produced by multiplying the second data element by the word of the final result sought that has been previously produced.