Long-term overfishing and environmental pollution has led to a high degree of change in Laizhou Bay fisheries resource structures. Since 1980, small pelagic fish have become the new dominant species in this area. These small pelagic fish play a connecting role in the food chain and are often one of the key groups in marine ecosystems. Research on the trophic level of Engraulidae and Clupeidae fish in Laizhou Bay based on stomach content analysis has provided useful but dated information. More up-to-date research is now necessary. Based on bottom trawl surveys in Laizhou Bay during summer and autumn, 2011, the stable isotope signatures of four Engraulidae and Clupeidae species revealed that the stable carbon isotope ratios ranged from 11.67‰, while stable nitrogen isotope ratios ranged from 8.54‰ to 15.95‰. ANOVA analysis revealed that among the four species (<0.05). Linear regression analysis between fork length and stable isotopic ratios showed that had significant ontogenetic variation in terms of δ¹⁵N ( Thrissa kammalensis did not (trophic level ranged from 2.80 to 4.88, with the average being 3.52±0.46; the trophic level ranged from 2.71 to 4.29, with the average being 3.34±0.33; the trophic level ranged from 3.38 to 4.42, with the average being 3.97±0.28; the trophic level ranged from 3.28 to 4.13, with the average being 3.76±0.23. According to the stable carbon and nitrogen isotope results, we can draw the following conclusions: (1) The stable carbon isotope values showed that trophic level range (-inhabits a wide depth range which is different to that of other pelagic fish; (2) The trophic level decreases with increasing fork length while that of increases with increasing fork length, no such changes were observed in the other two species; (3) The trophic level is about 0.7 times larger than that reported from the traditional stomach content analysis, which may be related to increased feeding on shrimp. The trophic level of the other three species was slightly higher according to the stable isotope results, but not significantly so.