Combined with actual engineering projects, the pre-laying management and stress condition during laying of the inventory subsea pipelines are analyzed. The key points in the application of inventory pipe materials are elaborated in detail from three aspects: assessment of storage and maintenance conditions, inspection and evaluation, and subsequent maintenance. Based on the stress analysis during laying, the influence of subsea pipeline specifications on laying construction is mainly discussed, and its influence on the changes of touch down point（TDP）, maximum bending moment, and strain is also analyzed. It is found that thinning of the pipe wall reduces the bending moment and strain at the overbend, lift-off point, and sagbend, while increasing the distance from the TDP. A laying dynamic analysis of 7 incoming flow directions and 4 wave periods is carried out. The results show that with decreasing wall thickness and increasing pipe diameter, the bending moment response at the lift-off point and sagbend is significant and exhibits a double-peak phenomenon, whereas the effect on tension response is minimal. Overall, strain and bending moment are more sensitive to oblique incoming flow and high wave periods. According to the fatigue analysis of slow laying and standby conditions, the maximum standby time and slow laying time are the shortest under 120° incoming flow direction and a wave period of 8 s. This also provides the fatigue and laying safety range for pipelines subjected to periodic variable loads during offshore pipeline laying.