PURPOSE: To edit the data consisting of plural data groups and to easily convert the data into an optional format in the same circuit constitution.

CONSTITUTION: A data format converting circuit consists of a data memory part 1 which individually stores plural data groups, a counter part 42 which performs a count-up operation by a clock signal, an address memory part 3 which can store an optional address code, and a data storing part 4 which can store the data read out by the address code. Then the data are read out of the part 1 against the address code in the count-up order and stored again in the part 4. Thus the data can be easily converted into an optional format.