Different postures are object of several kind of pain in the spine; this is evident in individuals who remain long hours working in inappropriate positions that can generate long-term injuries [1]. Currently, the detection of wrong posture is not headed to study every muscle involved in a particular work activity The use of these method generates a high variability on results as for observer, as for the patient. Is important to have strategies to reduce this variability. The electromyography technique is used to make an evaluation of posture, to do so, we have designed and implemented a wireless EMG, which can acquire the signal from six muscles in the back. Additionally ia data receiving software was implemented. This system performs the acquisition of the patient's muscles at his usual sitting position, making the record for a minute, then patient rests five minutes and data is acquired again, this time, with the patient on proper sitting posture. With the information a database is build. This database is used to determine whether a posture is appropriate or inappropriate. Finally the EMG is used to visualize and analyze the acquisition of the bioelectrical signal of the muscle in the software implemented, giving importance to the diagnosis, analysis make a statement about prevention and good posture, not only in students community, but in many other communities.