What is the the meaning of 'watashi wa anata ga suki desu yo?

you are almost correct because the meaning of watashi wa anata or aishite imasu is "I LOVE YOU" ♥♥♥

i think, [not completely sure] that it means "i like you" but I'm probably wrong..

watashi wa: I

anata ga: You

suki: like.

desu: indicates the end of the sentence

i think.. :D

Either "I like you" or "I love you". Could be either one.

-edit by another user-

it means "I like you!" the yo indicates emphasis on the statement, so in other Words it would be more like "I REALLY like you!" but if you were to be affectionate the Word love is ai or aishita so if it was a beginner speaking to you. Yes they said they liked you. but if they were advanced, they might mean your cute in that little kid way.

BTW The previous answer is correct.