Bit deviating out from producing formation by formation discontinuity some time happens in reservoir drilling with horizontal well. It is a high efficiency and economic construction method to use suspended sidetracking technology to sidetrack inside the reservoir formation with proper deviation angle. Chang-8 reservoir of Honghe oilfield is sand and mudstone interbed, it is easy to drill into mudstone interbed for horizontal construction. Back to the sandstone section, suspended sidetracking technology was applied, by optimization of sidetracking point, sidetracking bit and bottom hole assembly and with the rational deflection rate and sidetracking pressure, continuous drilling in reservoir sandstone was ensured with good oil gas show.