The straight answer is NO. There is nowhere in the bible where it was mandated that you must be baptized before you can partake of the communion. Although, in Matthew26:20-28 when Jesus ate the communion with the disciples, there was a very high tendency that they might have been baptized by John.

That may be one of the reasons why some Churches do not allow those that aren’t baptized to partake of the communion. Also, some feel that Matthew28:19 downwards is a command that puts baptism as the first sacrament before taking this Eucharistic meal. But when you interpret it like that, there won’t be any balance. I believe that the communion is a spiritual meal and nobody should be exempted except those that aren’t born again.

In the Old Testament, when God told the Jews to eat the Passover meal (which was a type of communion), He didn’t tell them to go dip themselves in the river first, He gave it to them as an ordinance that is mandatory for Jews without any special conditions attached. We are God’s children and when we come to the communion table, I don’t think God would send us away from the table because we’ve not been baptized. In fact, the command is that we should do it (referring to the communion) in remembrance of him.

I don’t see why baptism should be a hindrance because the bible didn’t say so, different churches have their beliefs about this issue but God’s word is supreme.