The problem to be solved is to provide a seat track assembly which is simple, easy to operate seat track assembly where locking is simplex and intact and which renders a smooth sliding of seat and the problem is solved by providing a seat track assembly with a lower channel, upper channel, latch bracket, latch pin, lever and sliding assemblies wherein sliding assemblies provide a streamlined sliding to the upper channel and at the desirable position latch pin engages with the lower channel to lock the seat track mechanism from moving further forward or rearward.