To　investigate　the　impacts　of　cold　surface　temperature　and　wet　air　state　on　the　freezing　process　and　phenomena　of　a　single　water　drop,　quantitative　measurements　were　carried　out　at　various　cold　plate　surface　temperatures　ranging　from　-165　degrees　C　to　-30　degrees　C.　The　covered　cold　surface　temperature　range　were　further　divided　into　ordinary-low　temperature　group　(-70　degrees　C　-　-30　degrees　C)　and　cryogenic　temperature　group　(-165　degrees　C　-　-100　degrees　C).　It　was　found　that　the　cold　surface　temperature　has　an　obviously　effect　on　the　drop　freezing　completion　time,　and　it　decreases　with　the　decrease　of　the　cold　plate　surface　temperature.　In　comparison　to　the　diameter　change　ratio　and　area　change　ratio,　the　height　change　ratio　of　a　drop　before　and　after　freezing　is　more　affected　by　cold　surface　temperature.　The　freezing　front　grows　upward　along　the　cold　surface,　gradually　changes　from　convex　to　concave　and　the　appearance　of　tip　singularity　indicates　the　completion　of　freezing.　The　internal　temperature　change　of　water　drops　is　greatly　influenced　by　air　temperature　and　cold　plate　surface　temperature,　though　it　will　finally　tend　to　be　stable.　These　findings　can　enrich　understanding　and　analyzing　water　drop　freezing　phenomena　under　different　cold　surface　temperature　conditions,　especially　under　cryogenic　conditions.