The invention relates to a memo pen. According to the memo pen, parts of the memo pen can be mutually buckled and embedded, the memo pen is convenient to carry, has multiple functions and can be usedfor writing in countless occasions; the portable memo pen is convenient to carry and is provided with a writing pen, a hand protecting pen cap, a rotary joint, a paper tube, a cover, a paper dischargeport, closing devices and buckling embedding devices; a buckling embedding type structure is adopted, the size is small, the appearance is simple and attractive, the memo pen can also be convenient to carry, the space is effectively saved and utilized, a pen refill can be replaced conveniently, and paper can be supplemented and carried conveniently so that writing can be facilitated; the memo pencan be used when something needs to be recorded in any places; the pen on the left side can be used as a normal pen for writing, the rotary pen cap with rubber can serve as a hand protector for the pen so that the problem that people are annoyed because the pen cap can not be found after the pen is used can be solved, the hand is protected, and meanwhile the daily trouble is solved; due to the fact that the paper tube on the right side is rolled, a large amount of paper can be placed, and the size is small so that the trouble that people need to take notes of important things but can not findthe paper in daily life can be avoided; the paper discharge port is designed, so that more convenience is brought to the users; the cover on the upper layer can be opened so that the paper can be replaced conveniently; and memo pen is convenient to carry and use.