To improve detection accuracy of tolerance of lift and working angle among cylinders in a control device 50 for a multiple cylinder internal combustion engine 1 including a purge means 20 and a variable valve train 30.

Detection process detecting tolerance of lift and working angle of valves 11 of the variable valve train 30 among cylinders is executed by estimating variation of intake air quantity among cylinders #1-#4 during operation in which lift and working angle are small such as light load operation in low rotation speed area and during purge control by the purge means 20. In other words, variation of intake air quantity among the cylinders #1-#4 caused by tolerance among the cylinders increases if purge control is performed when lift and working angle are small, quantity of evaporated fuel flowing in the cylinders #1-#4 varies by purging following that and torque variation among the cylinders #1-#4 becomes remarkably large. Consequently, detection accuracy of torque variation among cylinders #1-#4 is improved and intake air quantity variation among the cylinders can be accurately estimated.