Time-resolved plasma emission spectrum measurement system is established for pulsed laser deposition (PLD) device. In diamond-like carbon film deposition,the intensity of CII(426.7 nm) and CIII(229.7 nm) emission is observed. The result is that the intensity decreases with deposition time,and depends strongly on target′s surface. Keeping pulse energy and frequency constant,when the target is held,the emission intensity decreases more quickly than that when the target is rotated. The ratio of CIII emission intensity to that of CII is found increasing with time.