International theories in economy and finance areas expects a significant relation between forward and spot exchange markets where negotiations in forward market could predict the future of spot negotiations. However, this event is not noted at Brazilian exchange market (Brazilian real/dollar) as well at others international markets, especially at developed European markets. The reason would be in the presence of unobservable risk premiums. Therefore, the objective of that research is to evaluate the reason of that event does not run, utilizing some international researches, in order to test and to evaluate variables that could explain that rate s gap. The four variables selected for this study are: forward and spot bid-ask; the difference between forward and spot rates; and difference (real and absolute) between spot rate and spot rate built from purchase parity power condition. These variables are studied on one and twelve months horizons ans that selection has considered the presented significance in others international researches, for example libra/euro exchange rate, and because they are proxies of liquidity, time-varying and currency risk premium. The main results indicate that variables are significant despite the fact that some confiability tests show negative results. For instance, forward bid-ask and difference (real and absolute) between spot rate and spot rate built from purchase parity power condition presented a significance. The study is concluded affirming that some variables could help to explain that gap s rate. However, the existence of country risk does not allow the identification of a enough strong variable. Otherwise, it would enable investors to arbitrage and to profit without risk exposure.