Control Device for Internal Combustion Engine

A processor (B B) of a control device for an internal combustion engine operates a first combustion timing (MFB 50) or a first combustion period (IG _) in a cylinder of the internal combustion engine from a crank angle detected by a crank angle sensor A processor (B) operates a heat generation rate based on a first combustion timing or a first combustion period. A processor (B) operates in-cylinder pressure and in-cylinder unburned gas temperature based on the heat generation rate. A processor (B) operates a first combustion speed (laminar flow combustion speed SL) based on the in-cylinder pressure and the in-cylinder unburned gas temperature. A processor (B) learns a correspondence relationship between the first combustion speed and the first combustion timing or the first combustion period.