In this paper, a four-level sodium atomic medium coupled to a single-mode cavity is used to investigate the Goos-Ha¨nchen (GH) shift. Using the collective phase of the control fields and intensity of Rabi oscillation, the positive as well as negative GH-shift in transmission and reflection beams are examined. In the transmission beam, a maximum GH-shift of ±6λ is observed. Furthermore, GH-shift in both reflection and transmission beams in a four-level sodium atomic medium is significantly enhanced by photon number density as well as by the cavity coupling strength. By varying the collective phase of the control fields and the probe field frequency, GH-shift in reflection exhibits a maximum value of ±2λ. Our findings may open up significant applications in micro-optics, sensors, photonic crystals and nano-processor technology.