To know wheter the injury of the ligament may induce the meniscal tear, we statistically analyzed the incidence of meniscal tear with ?2 in cases of fresh and old(more than 3 months since injury) ligament injury in 419 joints of 407 adults who had been treated during the time between early 1984 and the end of 1992 in St. Mary's Hospital. The results were as follows: 1. The meniscal tear occurred more frequently in old ligament tear(44/70, 62.9%) than in fresh ligament tear(7/26, 26.9%) in cases of isolated ACL tear(P=0.062). 2. There was no significant difference between the old(10/34, 29.4%) and the fresh tear(24/96, 25.0%) in the combined ACL tear(P=0.615). 3. Overall ACL tear patients showed higher incidence of meniscal tear in the old ligament tear(54/1-4, 51.9%) than in the fresh ligament tear(31/122, 25.4%)(P=0.000). 4. The frequency of meniscal tear was very low in the isolated PCL tear(fresh tear: 0/14, old tear:1/17, 5.9%). In cases of combined PCL tear the incidence was rather higher in the fresh tear(11/33, 33.3%) than in the old tear(2/30, 6.7%)(P=0.015). 5. Overall PCL tear patients showed higher incidence of meniscal tear in the fresh ligament tear(11/47, 23.4%) than in the old ligament tear(3/47, 6.4%)(P=0.020). 6. The meniscal tear occurred more frequently in the ACL tear than in the PCL tear in both isolated(ACL : 85/96, 53.1%, PCL : 1/31, 3.2%) and overall ACL or PLC tear group(ACL : 85/226, 37.6%, PCL : 14/16.7%)(P=0.000). 7. The meniscal tear occurred less frequently in the isolated clootgeral ligament tear(9/94, 9.6%) than in the isolated cruciate ligament tear(52/127, 40.9%)(P=0.000). 8. The incidence of tear between the medial and the lateral meniscus showed no statistically significantly difference(P=0.215). From these results it would be suggested that the ACL tear, especially isolated tear may induce meniscal tear. On the other hand there was no statistically significant relationship between the incidence of meniscal tear and those of either PCL tear or collateral ligament tear.