Drilling is a complex and a high risk process which involves high financial cost. Over the years the number of horizontal wells and extended reach wells increased, due to the existence of deeper reservoirs, which are more difficult to access, in addition to the need of having an improvement in the oil production efficiency. Along with this increased complexity of drilling, unidentified operational problems end up being responsible for most of the non-productive time and daily cost increase. Thus, analyzing such problems it is very important to ensure safe operating conditions, optimize drilling operation, control causes/effects and have a faster and efficient decision-making capability. This paper presents a methodology to identify operational problems in order to optimize drilling operation using computer resources to predict torque, drag and hydraulic effects and later on to compare with the drilling data obtained in real time from mudlogging sensors and PWD (Pressure While Drilling). Cases were based on real time data from horizontal wells drilled in Campos Basis, Rio de Janeiro, and the problems were identified with unforeseen changes in drilling parameters trend. After studying the available well data, it was possible to diagnose several operational problems occurred during drilling, such as: lost circulation, stuck pipe, drill pipe washout and difficulty in drilling due to a poor hole cleaning, bit balling and drill string stick-slip vibration. In addition, it was also highlighted some examples that showed variations in the torque trend due to lithology changes.