We propose optical code division multiple access (OCDMA) over wavelength division multiplexing (WDM) in passive optical network (PON) based on Chebyshev-map chaotic spread spectrum. The system avoids the limitation of available wavelength channels and optical codes to the capacity, supports more subscribers by providing the same code at different wavelength channels. The scheme on Chebyshev-map chaotic spread spectrum is analyzed, consequently numerous-deterministic-regenerated chaotic sequences are provided. Performance analysis and simulations demonstrate the sequences have favorable correlation properties and bit error rate performance, and they can restrain the effect of multi-access interference.