Abstract: Double-pipe laying for a pipeline crossing in river tunnel was carried out. The two sides of the river tunnel were slope with wet tunnel floor and water emitting. Safety risk factors were identified such as large diameter, large tonnage, limit work space, big slope of both sides ground, poor ventilating in tunnel and poor lighting. Corresponding countermeasures were worked out. Supervising and management key points for pipeline construction in the limit space of river tunnel were clarified as follows: technical safety disclosure, temporary electricity supply, tunnel lifting operation, emergency drilling, etc.