An optoelectronics chip-to-chip interconnects system is provided, including at least one packaged chip to be connected on the printed-circuit-board with at least one other packaged chip, optical-electrical (O-E) conversion mean, waveguide-board, and (PCB). Single to multiple chips interconnects can be interconnected provided using the technique disclosed in this invention. The packaged chip includes semiconductor die and its package based on the ball-grid array or chip-scale-package. The O-E board includes the optoelectronics components and multiple electrical contacts on both sides of the O-E substrate. The waveguide board includes the electrical conductor transferring the signal from O-E board to PCB and the flex optical waveguide easily stackable onto the PCB to guide optical signal from one chip-to-other chip. Alternatively, the electrode can be directly connected to the PCB instead of including in the waveguide board. The chip-to-chip interconnections system is pin-free and compatible with the PCB. The main advantages of this invention are to use the packaged chip for interconnection and the conventional PCB technology can be used for low speed electrical signal connection. Also, the part of the heat from the packaged chip can be transmitted to the PCB through the conductors, so that complex cooling system can be avoided.