An engine valve timing controller controls a hydraulically driven variable valve timing mechanism, based on coolant temperature and intake air temperature. If coolant temperature and intake air temperature at engine startup are at least equal to an operation assurance oil temperature and an absolute value of the difference between the two temperatures is less than or equal to a prescribed temperature, then oil temperature is determined to be at least as high as the operation assurance oil temperature. Thus, the valve timing mechanism operates after coolant temperature rises to a first operation permission coolant temperature that is a temperature at which increasing the amount of internal EGR by increasing the amount of valve overlap is permitted. If these conditions are not satisfied, then valve timing mechanism operates after coolant temperature rises to a second operation permission coolant temperature that is a temperature at which oil temperature is definitely at least equal to the operation assurance oil temperature.