To　enhance　the　visibility　and　usability　of　images　captured　in　hazy　conditions,　many　image　dehazing　algorithms　(DHAs)　have　been　proposed.　With　so　many　image　DHAs,　there　is　a　need　to　evaluate　and　compare　these　DHAs.　Due　to　the　lack　of　the　reference　haze-free　images,　DHAs　are　generally　evaluated　qualitatively　using　real　hazy　images.　But　it　is　possible　to　perform　quantitative　evaluation　using　synthetic　hazy　images　since　the　reference　haze-free　images　are　available　and　full-reference　(FR)　image　quality　assessment　(IQA)　measures　can　be　utilized.　In　this　paper,　we　follow　this　strategy　and　study　DHA　evaluation　using　synthetic　hazy　images　systematically.　We　first　build　a　synthetic　haze　removing　quality　(SHRQ)　database.　It　consists　of　two　subsets:　regular　and　aerial　image　subsets,　which　include　360　and　240　dehazed　images　created　from　45　and　30　synthetic　hazy　images　using　8　DHAs,　respectively.　Since　aerial　imaging　is　an　important　application　area　of　dehazing,　we　create　an　aerial　image　subset　specifically.　We　then　carry　out　subjective　quality　evaluation　study　on　these　two　subsets.　We　observe　that　taking　DHA　evaluation　as　an　exact　FR　IQA　process　is　questionable,　and　the　state-of-the-art　FR　IQA　measures　are　not　effective　for　DHA　evaluation.　Thus,　we　propose　a　DHA　quality　evaluation　method　by　integrating　some　dehazing-relevant　features,　including　image　structure　recovering,　color　rendition,　and　over-enhancement　of　low-contrast　areas.　The　proposed　method　works　for　both　types　of　images,　but　we　further　improve　it　for　aerial　images　by　incorporating　its　specific　characteristics.　Experimental　results　on　two　subsets　of　the　SHRQ　database　validate　the　effectiveness　of　the　proposed　measures.