If you are talking about a feudalistic monarch, then yes. As I have written before about Marxist socialism, the idea of Marxist communism is that from capitalism, some form of collective ownership (the state in the form of the dictatorship of the proletariat, a commune, labor union, co-op, etc.) owns all the means of production on behalf of the common worker and pays everyone (in personal property, not private property) according to 'each according to his contribution' until you reach the final stage of communism and give people things 'each according to their ability and need' & create a stateless society.
Therefore, humanity only ever sets itself tasks that it can solve, because if you look more closely you will always find that the task itself only arises where the material conditions for its solution are already present or at least are in the process of becoming. In broad terms, Asian, ancient, feudal and modern bourgeois modes of production can be described as progressive epochs of economic social formation. -Karl Marx
Feudalism and feudalistic monarchy are part of the old world and are outdated according to Marx, as is hereditary ownership of the means of production (which is one of the reasons why Juche & modern North Korea is considered by many to not be Marxist state socialism, since it has become more of a 'hereditary dictatorship' where only those related to the current ruler have any chance of being in charge). Different people who aren't related can work their way up the state, labor union, or co-op to have more influence over the means of production and all the means of production are owned by a collective entity and if anyone leaves this entity/community, they lose direct say in the means of production. Marxist socialism is based around the idea of historical materialism, which casts monarchies as an ancient relic of mankind:
The rising bourgeoisie came into conflict with the feudal
system and with feudal rule, and as a product of its struggle
set up national republics, parliamentary states, constitutional
monarchies, which allowed free scope to the development of
capitalism, defended the interests of the bourgeoisie, stood
guard over their property, and so served to shape and consolidate the basis of capitalist society. -Historical Materialism by Maurice Cornforth
Feudalistic monarchies allowed people who swore oaths to have private property, only those related to the current monarch (or offered enough money in some circumstances) would have any say over the means of production, and serfs were slaves who had no healthcare/education provided by the collective entity. A monarchy with monarchs having absolute power would have no elections with all members of government appointed by the ruler, where even the authoritarian 'dictatorship of the proletariat' model of socialism in the USSR and Cuba allowed people to have limited say in their government by allowing them to move local members of the Communist Party from office if they got less than 50% of the vote. Any monarchy allowed in a Marxist socialist/communist system - autocratic, democratic, or otherwise - would be in name only with limitations on its power and little-to-no hereditary ties with the previous monarch for most of said monarchs successors; more of an elective monarchy of some form than an absolute one (and at that point, you may as well call the elected official a President, Premier, Head Union Representative, etc. instead of a king/queen).