Laboratory tests of the susceptibility/resistance of Culex tritaeniorhynchus F$_1$ larvae originated from the wild caught females collected at Juweol-dong, Gwangju city, Jeonla-namdo were carried out with 32 insecticides for detection of insecticide resistance in 1979∼1980, and the $LC_{50}$ and LC$sub$95/ values of each compound are presented as follows and compared to the values obtained from Sintain strain in Jeongup-gun, Jeonla-bugde in 1972. 1. It was found to be highly susceptible to all the synthetic pyrethroid compounds tested than any ether ones, decamethrin(NRDC 161) being the most susceptible(0.000021ppm of $LC_{50}$). 2. In case of organophosphorus compounds, the LC^{b 50} of chlorpyrifos was observed to be 0. 00626ppm which was the most susceptible values out of the 15 kinds of OP compound, though it was 22 times as less susceptible as value 0.00028ppm in 1972. The $LC_{50}$ values of the other OP compounds and folds of resistance at the $LC_{50}$ level compared to larvae in 1972 and given in descending order of toxicity: EPN 0.015ppm (28-fold), diazinon 0.161ppm (8-fold), fenitrothion 0.3646ppm(46-fold), naled 0.418ppm (15-fold), fenthion 0.916ppm(195-fold), dichlorvos 1.309ppm (93-fold) and malathion 2.349ppm (87-fold). 3. In organochlorine compounds, the $LC_{50}$ value of DDT was 0.0281ppm, lindane 0.0s62ppm and dieldrin 0.0716ppm, which were converted about 3∼6 times as more susceptible as compared to 1972 values. 4. C. tritaeniorhynchus larvae were not susceptible to cabramates, the $LC_{50}$ value of bendicarb being 0.526ppm, BPMC 0.282ppm and propuxur 0.812ppm. But $LC_{50}$ of cartap (Padan) was 0.125ppm, and its slope was found to be steep. 5. The $LC_{50}$ value of combined-compound of fenitrothion-permethrin (10 : 1) was 0.0031ppm which was as 117-fold toxic as that of fenitrothion alone, and that of fenitrothion-tetramethrin (10 : 1) was 0.38ppm which was very similar to that of fenitrothion alone but LC$sub$95/value (1.02ppm) was 18 times more susceptible.