An information recording technique for forming a recording mark with a multi-pulse sequence, which is increased by one pulse with an irradiation power Pw for every increase of 2T in a temporal length nT of the recording mark is provided. Particularly, this technique realizes a recording strategy that is simple in its configuration but is capable of improving the consistency of mark shapes in forming the recording marks when the value n of the temporal length nT is an odd number. More specifically, when n is an odd number and n≧7, a period from the fall of a first pulse to the fall of a second pulse is set to 2.5 T and a period corresponding to a last pulse is set to (2+δ1o)T where the value of δ1o is optimized within a range of 0