Yes. There are several persons in God because this word "person" signifies in God a relation as subsisting in the divine nature.
There are several real relations in God; and hence it follows that there are also several realities subsistent in the divine nature: which means that there are several persons in God.
The supreme unity and simplicity of God exclude every kind of plurality of absolute things, but not plurality of relations. Because relations are predicated relatively, and thus the relations do not import composition in that of which they are predicated.