A foaming agent comprising an organic amine salt compound of the following general formula or a mixture of organic amine salt compounds of the following general formula: A n- [B m+] p in the above formula, A n- is a CO 2 -donating anion with a valence of -n, wherein n = 1 or 2; each B m+ independently comprises: ammonium ion of +1 valence ( + NH 4), hydrazinium ion of +1 valence (H 3 + N-NH 2), hydrazinium ion of +2 valence (H 3 + N-NH 3 +), or, one or more organic amine cations having m of - + NR 3 R 4 H groups and - + NR 3 H- groups; wherein m = 1-5; 0 < p ≤ n m; and wherein A n- is one or more selected from the group consisting of the following anions: carbonate: CO 3 2-; and bicarbonate: HO-COO -; wherein, R 3 and R 4 is independently chosen from the group consisting of: H, R, C 1 -C 7 aliphatic hydrocarbyl group optionally substituted by hydroxyl or amino or halogen, C 3 -C 7 cycloaliphatic hydrocarbyl group optionally substituted by hydroxyl or amino or halogen, and, C 6 -C 10 aromatic hydrocarbyl group optionally substituted by hydroxyl or amino or halogen; provided that: the compound of general formula has at least one R group linked to N atom; wherein the R group is one or more groups selected from the group consisting of: H[OCH(R 1a)CH(R 2a)]q-; H[OCH(R 1a)CH(R 2a)CH(R 3a)] q -; and H[OCH(R 1a)CH(R 2a)CH(R 3a)CH(R 4a)] q -; wherein the value of q is q = 1-4; R 1a, R 2a, R 3a and R 4a each independently is selected from the group consisting of: H, C 1 -C 7 aliphatic hydrocarbyl group optionally substituted by hydroxyl or amino or halogen, C 3 -C 7 cycloaliphatic hydrocarbyl group optionally substituted by hydroxyl or amino or halogen, and, C 6 -C 10 aromatic hydrocarbyl group optionally substituted by hydroxyl or amino or halogen; wherein, said organic amine compound is an organic amine compound having 2-20 carbon atoms; wherein, the water content in the foaming agent is 5-40wt%; and the total content of the compounds of the general formula and water in the foaming agent is 70-100wt%, based on the total weight of the foaming agent; and wherein, the organic amine salt compound of the general formula or the mixture of organic amine salt compounds of the general formula contains 40-96wt% of salt of monoalkanolamines and salt of di-alkanolamines, based on the total weight of the compound of general formula or of the mixture. in the above formula, A n- is a CO 2 -donating anion with a valence of -n, wherein n = 1 or 2; each B m+ independently comprises: ammonium ion of +1 valence ( + NH 4), hydrazinium ion of +1 valence (H 3 + N-NH 2), hydrazinium ion of +2 valence (H 3 + N-NH 3 +), or, one or more organic amine cations having m of - + NR 3 R 4 H groups and - + NR 3 H- groups; wherein m = 1-5; 0 < p ≤ n m; and wherein A n- is one or more selected from the group consisting of the following anions: carbonate: CO 3 2-; and bicarbonate: HO-COO -; carbonate: CO 3 2-; and bicarbonate: HO-COO -; wherein, R 3 and R 4 is independently chosen from the group consisting of: H, R, C 1 -C 7 aliphatic hydrocarbyl group optionally substituted by hydroxyl or amino or halogen, C 3 -C 7 cycloaliphatic hydrocarbyl group optionally substituted by hydroxyl or amino or halogen, and, C 6 -C 10 aromatic hydrocarbyl group optionally substituted by hydroxyl or amino or halogen; provided that: the compound of general formula has at least one R group linked to N atom; wherein the R group is one or more groups selected from the group consisting of: H[OCH(R 1a)CH(R 2a)]q-; H[OCH(R 1a)CH(R 2a)CH(R 3a)] q -; and H[OCH(R 1a)CH(R 2a)CH(R 3a)CH(R 4a)] q -; H[OCH(R 1a)CH(R 2a)]q-; H[OCH(R 1a)CH(R 2a)CH(R 3a)] q -; and H[OCH(R 1a)CH(R 2a)CH(R 3a)CH(R 4a)] q -; wherein the value of q is q = 1-4; R 1a, R 2a, R 3a and R 4a each independently is selected from the group consisting of: H, C 1 -C 7 aliphatic hydrocarbyl group optionally substituted by hydroxyl or amino or halogen, C 3 -C 7 cycloaliphatic hydrocarbyl group optionally substituted by hydroxyl or amino or halogen, and, C 6 -C 10 aromatic hydrocarbyl group optionally substituted by hydroxyl or amino or halogen; wherein, said organic amine compound is an organic amine compound having 2-20 carbon atoms; wherein, the water content in the foaming agent is 5-40wt%; and the total content of the compounds of the general formula and water in the foaming agent is 70-100wt%, based on the total weight of the foaming agent; and wherein, the organic amine salt compound of the general formula or the mixture of organic amine salt compounds of the general formula contains 40-96wt% of salt of monoalkanolamines and salt of di-alkanolamines, based on the total weight of the compound of general formula or of the mixture.