An inbred corn line, designated LM3, is disclosed. The invention relates to the seeds of inbred corn line LM3, to the plants and plant parts of inbred corn line LM3 and to methods for producing a corn plant, either inbred or hybrid, by crossing inbred corn line LM3 with itself or another corn line. The invention also relates to products produced from the seeds, plants, or parts thereof, of inbred corn line LM3 and/or of the hybrids produced using the inbred as a parent. The invention further relates to methods for producing a corn plant containing in its genetic material one or more transgenes and to the transgenic plants produced by that method and to methods for producing other inbred corn lines derived from inbred corn line LM3.