SAFE DRIVING ASSIST DEVICE

A safe driving assist device for a vehicle includes an inter-vehicle distance detector, a preceding vehicle speed detector, a preceding vehicle deceleration detector, an assumed deceleration calculator, and a vehicle controller. The inter-vehicle distance detector detects an inter-vehicle distance between the vehicle and a preceding vehicle traveling ahead of the vehicle. The preceding vehicle speed detector detects a traveling speed of the preceding vehicle. The preceding vehicle deceleration detector detects a deceleration of the preceding vehicle based on the traveling speed of the preceding vehicle. The assumed deceleration calculator calculates an assumed deceleration when the preceding vehicle enters a curve, based on the inter-vehicle distance, the traveling speed of the preceding vehicle, and curve information acquired from map information. The vehicle controller performs control to reduce a speed of the vehicle when the deceleration of the preceding vehicle is greater than the assumed deceleration.