A secure equijoin system, wherein Z N is assumed to be a finite ring formed of a set of integers from 0 to N-1 (N is an integer greater than or equal to 1), m and n are assumed to be integers greater than or equal to 1, a and b are assumed to be integers greater than or equal to 2, and p i (1 ≤ i ≤ m; p 1,.., p m differ from each other), v i,j (1 ≤ i ≤ m, 2 ≤ j ≤ a), q i (1 ≤ i ≤ n), and u i,j (1 ≤ i ≤ n, 2 ≤ j ≤ b) are assumed to be elements, which are not 0, of the finite ring Z N, [[x]] is assumed to be a value obtained by concealing x ∈ Z N, × is assumed to denote a multiplication algorithm of obtaining [[c]] in a concealed state, c = a × b when provided with [[a]] and [[b]] of a, b ∈ Z N and <π> is assumed to denote the execution of a permutation π by secure computation, the secure equijoin system is configured with three or more secure equijoin devices and generates a table J having n rows and a+b-1 columns from a table L having m rows and a columns with elements being concealed and a table R having n rows and b columns with elements being concealed, and the secure equijoin system includes a first permutation generating means that generates a permutation <σ> by performing a stable sort on an element sequence ([[p 1]],.., [[p m]], [[q 1]],.., [[q n]], [[p 1]],.., [[p m]]) which is generated from a first column ([[p 1]],.., [[p m]]) of the table L and a first column ([[q 1]],.., [[q n]]) of the table R, a first column generating means that generates second to a-th columns of the table J by generating, for j = 2,.., a, an element sequence [[f]] = ([[v 1,j]],.., [[v m,j]], [],... [], [[-v 1, j]],.., [[-v m,j]]) by using a j-th column ([[v 1,j]],.., [[v m,j]]) of the table L and an element sequence ([],.., []) obtained by arranging n [], an element sequence [[g]] = [[σ([[f]])]] from the element sequence [[f]] by using the permutation <σ>, an element sequence [[g']] = PrefixSum([[g]]) by calculating a prefix sum of the element sequence [[g]], an element sequence [[f']] = [[σ -1 ([[g']])]] from the element sequence [[g']] by using an inverse permutation <σ -1 > of the permutation <σ>, and a j-th column ([[v' 1,j]],.., [[v' n,j]]) = ([[f' m+1]],.., [[f' m+n]]) of the table J by extracting a partial element sequence ([[f' m+1]],.., [[f' m+n]]) of m+1- to m+n-th elements of the element sequence [[f']], a join-result element sequence generating means that generates an element sequence [[fl]] = ([],.., [], [],.., [], [[-1]],.., [[-1]]) by using an element sequence ([],.., []) of m [] and an element sequence ([],.., []) of n [], an element sequence [[gl]] = [[σ([])]] from the element sequence [[fl]] by using the permutation <σ>, an element sequence [[g1']] = PrefixSum([]) by calculating a prefix sum of the element sequence [[gl]], an element sequence [[f1']] = [[σ -1 ([[g1']])]] from the element sequence [[g1']] by using the inverse permutation <σ -1 >, and a join-result element sequence ([[e 1]],.., [[e n]]) = ([[f1' m+1]],.., [[f1' m+n]]) by extracting a partial element sequence ([[f1' m+1]],.., [[f1' m+n]]) of m+1-to m+n-th elements of the element sequence [[f1']], a second column generating means that generates a+1- to a+b-1-th columns of the table J by generating, for j = a+1,.., a+b-1, a j-th column ([[u' 1,j-a+1]],.., [[u' n,j-a+1]]) = ([[e 1]] × [[u 1,j-a+1]],.., [[e n]] × [[u n,j-a+1]]) of the table J by using the join-result element sequence ([[e 1]],.., [[e n]]) and a j-a+1-th column ([[u 1,j-a+1]],.., [[u m,j-a+1]]) of the table R, and a third column generating means that generates a first column ([[q' 1]],.., [[q' n]]) = ([[e 1]] × [[q 1]],.., [[e n]] × [[q n]]) of the table J by using the join-result element sequence ([[e 1]],.., [[e n]]) and the first column ([[q 1]],.., [[q n]]) of the table R, and each of the above means is jointly computed by the three or more secure equijoin devices. an element sequence [[f]] = ([[v 1,j]],.., [[v m,j]], [],... [], [[-v 1, j]],.., [[-v m,j]]) by using a j-th column ([[v 1,j]],.., [[v m,j]]) of the table L and an element sequence ([],.., []) obtained by arranging n [], an element sequence [[g]] = [[σ([[f]])]] from the element sequence [[f]] by using the permutation <σ>, an element sequence [[g']] = PrefixSum([[g]]) by calculating a prefix sum of the element sequence [[g]], an element sequence [[f']] = [[σ -1 ([[g']])]] from the element sequence [[g']] by using an inverse permutation <σ -1 > of the permutation <σ>, and a j-th column ([[v' 1,j]],.., [[v' n,j]]) = ([[f' m+1]],.., [[f' m+n]]) of the table J by extracting a partial element sequence ([[f' m+1]],.., [[f' m+n]]) of m+1- to m+n-th elements of the element sequence [[f']], an element sequence [[fl]] = ([],.., [], [],.., [], [[-1]],.., [[-1]]) by using an element sequence ([],.., []) of m [] and an element sequence ([],.., []) of n [], an element sequence [[gl]] = [[σ([])]] from the element sequence [[fl]] by using the permutation <σ>, an element sequence [[g1']] = PrefixSum([]) by calculating a prefix sum of the element sequence [[gl]], an element sequence [[f1']] = [[σ -1 ([[g1']])]] from the element sequence [[g1']] by using the inverse permutation <σ -1 >, and a join-result element sequence ([[e 1]],.., [[e n]]) = ([[f1' m+1]],.., [[f1' m+n]]) by extracting a partial element sequence ([[f1' m+1]],.., [[f1' m+n]]) of m+1-to m+n-th elements of the element sequence [[f1']],