A heat sink element coupling structure comprised of a "+" or a "+"-shaped horizontal offset disposed on the upper and lower or left and right two sides or a certain position on the lateral edge at the center portion of an L-shaped or a horizontally oriented U-shaped heat sink unit (element) plate. The structure includes inverted U-shaped or U-shaped appendages situated at the anterior section of the horizontal offsets as well as one or two wing-shaped lock tabs formed at the two sides or either the left or the right side of the inverted U-shaped or U-shaped appendages. Also included in the structure are one or two cutaways at the two sides or either the left or the right side of the horizontal offsets and a downward or upward lock tab at the two sides or the either left or right of the anterior edge of the horizontal offsets. The wing-shaped lock tabs or lock tabs of each coupling structure at the two sides of one heat sink unit (element) are fitted onto the horizontal offsets of the next correspondingly situated heat sink unit (element) such that the one or two wing-shaped lock tabs or lock tabs on the front heat sink unit (element) become engaged onto the lateral edge of the adjacent other heat sink unit (element), the horizontal offsets at the two lateral edges of the its plate or the cutaway at one side, thereby enabling several or numerous heat sink elements to be interconnected at fixed horizontal distances and positions.