This investigation was conducted at EL-Borollous district, kafr EL-Sheikh Governorate, North Nile Delta area. The aim of this study was to find out the influence of air temperature on the corresponding transparent polyethylene low tunnel temperature as well as soil temperature at successive depths of 5, 10, 15 and 20 cm. Therefore, air and soil temperatures in the open field and under clear polyethylene low tunnel were recorded daily at 8 a.m., 11 a.m., 2 P.m. and 5 P.m. during the period of tunnel implementation (1^st of Nov. through 31^st of March, 2003 & 2004). Main results could be listed as follows: -     Both air and soil temperature raised gradually from 8.0 a.m. till 2.0 p.m. and then declined. -     The gap between maximum and minimum temperature was high for air at both open environment and under tunnel. This range was also higher at surface soil depth and it declined gradually with increasing soil depth.      -     The most affected soil depth in relation with air temperature was the upper 5.0 cm.  -     The relations between air and soil temperature could be expressed as follows: 1- Low air temp. under tunnel (8. a.m), T temp 8 = 0.9066 (low open air temp 8 a.m, A tem 8) + 1.4388          R²  = 0.8874 2- Open field soil temp at 5 cm. depth = 0.7006  (A tem 8) +  4.6587          R²  = 0.9065 3- Tunnel soil temp, tunnel at 5 cm. depth (STD5) = 0.7141 (A tem 8) +  4.6101          R²  = 0.759 4- STD5 = 0.6407 (T tem 8) + 5.8751          R²  = 0.7022              The listed equations provide the concern specialists of researchers, extension workers and / or farmers, with valuable knowledge about tunnel temperature for both air and soil as well as the corresponding values in the open surrounding conditions. Such data are useful to determine which crop should be cultivated based on soil temperature at the most dynamic depth of 5 cm.