With the seeds of Lycium ruthenicum as the experimental material, the neutral salt NaCl, Na₂SO₄ and the alkaline salt NaHCO₃, Na₂CO₃ were simulated to form neutral compound salt L (1∶1∶0∶0), moderately basic compound salt M (1∶9∶9∶1) and severely basic compound salt H (9∶1∶1∶9) according to the proportion of alkaline salts from small to large, we used the Paper Germination experiment to study the effects of exogenous melatonine (0.1, 0.3, 0.5, 1.0 mmol/L) on seed germination and seedling growth of L. ruthenicum seeds under different saltalkali composition (L, M, H) and saltalkali concentration (50, 100, 200 mmol/L) combined stress. The results showed: (1) the growth phenotype of L. ruthenicum seedlings is obviously weakened with the increase of salinealkali concentration and alkaline salt proportion; Appropriate concentration of exogenous melatonine (0.1, 0.3, 0.5 mmol/L) could alleviate the damage of salinealkali stress on seedling growth to a certain extent, while excessive concentration of exogenous melatonine (1.0 mmol/L) will aggravate the damage. At the same time, the application of exogenous melatonine(MT) significantly increased the number of lateral roots of L. ruthenicum seedlings. (2) The germination process of L. ruthenicum seeds is closely related to salinealkali composition, salinealkali concentration and MT concentration. With the increase of the saltalkali concentration and the proportion of alkaline salt, the initial time of germination of L. ruthenicum seeds is delayed, and the total germination time is shortened; Applying an appropriate concentration of exogenous MT can advance the germination start time of L. ruthenicum seeds under salinealkali stress and prolong the total germination time. (3) In the L compound salt treatment, with the increase of the saltalkali stress concentration, the germination rate (GR), germination potential (GP), germination index (GI), vitality index (VI), shoot length (SL), root length (RL) all increase first and then decrease; In the M and H compound saltalkali treatments, all germination indexes showed a gradual decrease with the increase of the saltalkali stress concentration. (4) Exogenous MT has obvious “lowpromoting highsuppressing” phenomenon on the germination indexes of L. ruthenicum seeds, In the L compound salt, under the stress of 3 kinds of salt concentration, when the MT concentration is 0.1 and 0.3 mmol/L, it can promote GR, GP, GI, VI, SL and RL, and the comprehensive promotion effect of 0.1 mmol/L is the best, and when the MT concentration is 0.5 and 1.0 mmol/L, it has a inhibitory effect on GP, GR, GI and VI, when the MT concentration is 1.0 mmol/L, it has a inhibitory effect on SL and RL; Among the M and H compound saltalkali, under the stress of 3 kinds of saltalkali concentration, when the MT concentration is 0.1, 0.3, 0.5 mmol/L, it has a promoting effect on all indicators, and the comprehensive promotion effect of 0.3 mmol/L is the best, and when the MT concentration is 1.0 mmol/L, it has a inhibitory effect. Studies have shown that lowconcentration neutral compound salt treatment can promote seed germination and seedling growth of L. ruthenicum to a certain extent, while highconcentration neutral compound salt and moderate and severely alkaline compound salt have an inhibitory effect. Exogenous melatonin has a significant dose effect on the alleviation of seed germination and seedling growth of L. ruthenicum under saltalkali stress. When the melatonin concentration is 0.1 mmol/L, the comprehensive promotion effect on neutral complex salt stress is better, and melatonin at 0.3 mmol/L, it has the best promoting effect on moderate and severe alkaline complex salt stress.