My understanding was that their canon was the same as the Catholics. Perhaps one of our Coptic members can correct this if it is untrue.
I know Ps 151 is used on Bright Saturday, and I don't think that's in the Catholic canon, but I could be wrong. Don't remember offhand if there are any other differences.
The confusion might be because unlike Catholics, we don't accept the deuterocanonical books as equal to the protocanonical books. In St. Athanasius' paschal letter, the deuterocanonicals are listed as profitable to read, rather than listed with the protocanonicals. Practically speaking though, Sirach, Wisdom, Tobit, Ps 151, Susanna, Bel Dragon, Baruch, and the song of the three holy youths are all read liturgically in either Lent or Pascha week, so I don't think any argument could be made that they aren't accepted.