AbstractWe have measured the annual parallax of the water maser source associated with star forming region NGC2264 from observations with VLBI Exploration of Radio Astrometry (VERA). We detected masers at V_LSR = 7.2 km s⁻¹. We discussed its driving sources of detected maser spots. One of the maser spots was associated with a centimeter continuum source observed with VLA. Neither optical, infrared nor X-ray sources is catalogued near the spot. The other maser spot is located close to an X-ray source, although there is no optical or infrared counterpart. The proper motion of the former spot was (μ_α, μ_δ) = (23.91 ± 4.29, −29.81 ± 4.27) and the proper motion of latter spot was (μ_α, μ_δ) = (−0.96 ± 0.58, −6.05 ± 3.06). For the latter spot, the peculiar motion is ∼ 150 km s⁻¹ and it has the high velocity and this may be a jet or an outflow from a young star. The observed parallax is 1.365 ± 0.098 mas, corresponding to the distance of 738⁺⁵⁷₋₅₀ pc. This value is constant with the photometric distance of NGC2264 previously measured. The fitting result of the parallax is shown in figure 1. We also observed in NH₃ (1,1), (2,2), (3,3) lines of NGC2264 with the Kashima 34m telescope. We estimated the star formation efficiency (SFE) of NGC2264 from the dense molecular mass of NH₃ and the stellar mass calculated by Teixeira et al. (2012). The SFE is 9 – 12% which is consistent with previous results.