In this paper, we study the bi-isolation phenomena in the d.c.e. degrees and prove thai there are c.e. degrees c_1 < c_2 and a d.c.e. degree d ∈ (c_1, c_2) such that (c_1, d) and (d, c_2) contain no c.e. degrees. Thus, the c.e. degrees between c_1 and c_2 are all incomparable with d. We also show that there are d.c.e. degrees d_1 < d_2 such that (d_1, d_2) contains a unique c.e. degree.
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