The invention discloses a construction technique of wrapping concrete outside a steel member. The construction technique adopts the steps: firstly, concrete is prepared; secondly, a first layer of reinforcing steel bars is prepared outside the steel member, and the distance between every two adjacent reinforcing steel bars is not less than 80 mm; thirdly, the concrete is sprayed to the surface ofthe steel member, and the thickness of the concrete is controlled between 70 mm to 100 mm; fourthly, a second layer of reinforcing steel bars is prepared outside the concrete layer; fifthly, the concrete is sprayed according to the third step; and sixthly, the fourth step and the fifth step are repeated according to the requirements, and the concrete is cured conventionally. The construction technique can avoid the problems in the existing casting method for wrapping concrete outside the steel member, mould plates are not required or less mould plates are required, therefore the investment isgreatly reduced and the construction period is shortened.