Provided is a lead frame that may include a frame, a lead structure, and a dam bar. The frame may include a plurality of openings configured to receive semiconductor chips. The lead structure may be in the openings. The lead structure may also include inner leads and outer leads. The inner leads may be configured to electrically connect to the semiconductor chips and the outer leads may extend from the inner leads. In example embodiments, the lead structure may extend in a first direction. The dam bar may be arranged between the inner leads and the outer leads. In accordance with example embodiments, the dam bar may extend along a second direction which is substantially perpendicular to the first direction. In example embodiments, the dam bar may have a first strength-reinforcing portion extending along the second direction. Also provided is a semiconductor package having the lead frame.