Abstract: Artificial nitrogen fertilizer has been one of the most essential supplements for plant growth. Nitrogen can be an indispensable element for chlorophyll synthesis of most crops. However, the high nitrogen application rate in tomato production has posed a serious threat to the nitrogen utilization rate and ecological environment in recent years. In this study, data acquisition was proposed to obtain a suitable range of nitrogen concentration for tomato growth using chlorophyll fluorescence under the requirements of precision fertilization. Seven test groups were set with the nitrogen concentration gradient (3.5, 7.0, 10.5, 14.0, 17.5, 21.0, and 24.5 mmol/L), according to the nitrogen content in the formula of Japanese garden test nutrient solution (17.5 mmol/L). The contents of other elements were the same as the formula in the experiment. The parameters of chlorophyll fluorescence and dry matter were obtained for the leaves of tomatoes that were treated with seven nitrogen concentrations. A systematic analysis was made to determine the change of dry weight, leaf nitrogen, phosphorus, and potassium concentration with the nitrogen concentration. As such, the nitrogen concentration of the nutrient solution was between 7.0-10.5 mmol/L suitable for the tomato plant growth. A correlation analysis of chlorophyll fluorescence parameters was carried out for the appropriate nitrogen concentration range using the maximum mutual information coefficient. The results showed that there were the most correlated parameters of chlorophyll fluorescence with the nitrogen concentration, including ABS/RC (absorbed flux absorbed by reaction center), PIABS(Performance Index based on ABS), ETo/RC (electron transport flux captured by reaction center), and Fv/Fo (Potential activity of photosystems), whose Maximum Information Coefficient (MIC) values were all greater than 0.4. The Fv/Fo was found to be the most suitable chlorophyll fluorescence parameter in the proper nitrogen concentration range for plant growth. The response curve of Fv/Fo to nitrogen concentration was obtained by the polynomial fitting the discrete points of Fv/Fo response to nitrogen concentration. The curvature curve was calculated using the u-chord curvature of the curve, and the point at which the curvature began to increase was taken as the curvature characteristic point. The curvature characteristic point and the maximum point were used as the lower limit and upper limit for the regulation interval of nitrogen concentration. The suitable nitrogen concentration range was 7.2-9.8 mmol/L for tomato growth. In this case, the dry matter and physiological amounts remained at a high level, and the coefficient of variation was the lowest, indicating that there was little effect of nitrogen concentration on the tomato growth. Specifically, the tomato dry weight, P and K concentration in the leaves increased by 33.8%, 10.2%, and 11.3% on average, respectively, the N concentration in the leaves decreased by 0.8% on average, and the nitrogen application decreased by 51.4%, compared with Japan garden test nutrient solution treatment. There was also a higher plant dry weight, as well as the leaf N, P, and K contents, indicating balanced nutrient absorption. Consequently, a reasonable and accurate interval of nitrogen concentration can be achieved for crop growth. This finding can provide a theoretical basis for the accurate regulation of nitrogen application rate, further realizing the long-term monitoring of leaves without destructive physical and chemical testing.