I do not believe that the Catholic Church prohibits tattoos specifically, but I could be wrong.
Tattoos in the times of the Israelites were used by pagans in ancestor-worship.
HOWEVER, in the New Testament, Jesus Christ says:
[quote=1 Cor. 3:16-17]Know ye not that ye are the temple of God, and that the Spirit of God dwelleth in you? If any man defile the temple of God, him shall God destroy; for the temple of God is holy, which temple ye are.
Also, in the first book of the Bible, Gen. 1:26:
[quote=Gen. 1:26]And God said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth.
So, based on these references, tattoos don’t really seem prudent for a Christian. However, one or two small ones probably shouldn’t be a problem but you may want to speak to your priest or spiritual director to see why you want to get one in the first place…