Finite element theory was taken to do a research on a through CFST (concrete-filled steel tube) arch bridge and a change rule of the bridge's natural vibration frequency was found when its suspenders were tensioning. Through three tension schemes, after solving the first fifteen orders of the natural vibration frequency of each condition and drawing the change curve and analyzing the effect of different suspender tension order on the natural vibration frequency, we come to the conclusion: different suspender tension order will have no effect on the natural vibration frequency when the bridge is completed but when it is constructing, which mainly shows that both the first three and eight to thirteen orders of the natural vibration frequency are discrepant; different location of suspenders has different affection degree on the natural vibration frequency of the bridge. The conclusion has reference value for bridge construction.
