The invention provides a heat dissipation structure of a module spot lamp. The heat dissipation structure includes lamp modules, shell assemblies and a pressing cover, the shell assemblies are a plurality of detachable shells, the shell assemblies are arranged as the multiple detachable shells, meanwhile, the lamp modules are detachably mounted in the shell assemblies, the pressing cover is used for packaging, thus the module spot lamp can be conveniently disassembled and maintained, meanwhile, the purpose of good heat dissipation can further be achieved, the shell assemblies are all set as copper materials, and heat energy generated by the lamp modules is further improved; and the lamp modules and the shell assemblies are separately produced and manufactured, the maintenance cost is greatly saved, quick maintenance after the fault of the lamp modules is convenient, and meanwhile, the purpose of no needing to replace the entire lamp is achieved. The shell assemblies are arranged as themultiple detachable shells, the maintenance efficiency of the shell assemblies is greatly improved, and better heat dissipation is further realized.