Abstract: With a titanium:sapphire ring laser in conjunction with a White cell and signalreceiving system,the high-resolution spectrum of O₂ A-band in line overlapping region(13162.85～13165.33cm^-1)has been measured and analysed,obtaining widths and strengths ofeight absorption lines and the first showing that line coupling not only effects on the absorptioncoefficient but also on the measurement accuracy of line-width and line-strength.At 0.1 MPaand 1 km absorption length,the greatest effect of line coupling on measurement value ofline-width and line-strength,and on transimission can reach 8.8%, 16.6%,and 8.3%,respectively.