The Bulgaria winger - on a season-long loan at Celtic Park from Aston Villa - was punished by the SFA having been found guilty of using "offensive, insulting and abusive language of a racist nature" towards Aberdeen's Shay Logan when making his Celtic debut in September.
An appeal was launched and Tonev was free to continue playing while a tribunal considered the decision.
However, the original ruling has been upheld and Tonev will now serve his punishment, with one match of his suspension having already been served.
"The appeal has been rejected and an immediate seven-match suspension will be applied [with one match having already been served]," read a statement from the SFA.
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