Neuronal growth cones navigate over long distances along specific pathways to find their correct targets. Pie prevailing opinion is that growth cones appear to be guided by four different mechanisms: contact attraction, chemoattraction, contact repulsion, and chemorepulsion. In contrast to existing methods, we use optical trap to guide: neuronal growth. The optical trap is a non-contact manipulation technology which is increasingly used for micromanipulation of living cells and organisms. An intense light gradient near the focal region of a near-infrared laser beam gives, rise to forces that make possible optical trapping and manipulation of a variety of micron-sized objects. In the developing nervous system, microtubule and actin play a fundamental role. To change the microtubule polymerization by control the density of tubulins or exerting a persistent force on the whole growth cone, we have shown experimentally that we can use optical trap to guide the growth direction of a neuron. In order to guide the neuronal growth direction, a self-contrived optical trap is placed in front of a specific area of the edge of the cell's growth cone. We turned the neuronal growth direction and guided it to the direction we expected. Control over neuronal growth is a fundamental objective in neuroscience and guiding neuronal growth with optical trap may be very important for the formation of neural circuits as well as nerve regeneration.