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Let <i>G</i> be a connected graph; the edge Mostar index <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>M</mi><msub><mi>o</mi><mi>e</mi></msub><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow></mrow></semantics></math></inline-formula> of <i>G</i> is defined as <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mstyle scriptlevel="0" displaystyle="true"><mrow><mi>M</mi><msub><mi>o</mi><mi>e</mi></msub><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow><mo>=</mo><munder><mo>∑</mo><mrow><mi>e</mi><mo>=</mo><mi>u</mi><mi>v</mi><mo>∈</mo><mi>E</mi><mo>(</mo><mi>G</mi><mo>)</mo></mrow></munder><mrow><mo>|</mo><msub><mi>m</mi><mi>u</mi></msub><mrow><mo>(</mo><mi>e</mi><mo>)</mo></mrow><mo>−</mo><msub><mi>m</mi><mi>v</mi></msub><mrow><mo>(</mo><mi>e</mi><mo>)</mo></mrow><mo>|</mo></mrow><mo>,</mo></mrow></mstyle></semantics></math></inline-formula> where <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>m</mi><mi>u</mi></msub><mrow><mo>(</mo><mi>e</mi><mo>)</mo></mrow></mrow></semantics></math></inline-formula> and <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>m</mi><mi>v</mi></msub><mrow><mo>(</mo><mi>e</mi><mo>)</mo></mrow></mrow></semantics></math></inline-formula> denote the number of edges in <i>G</i> that are closer to vertex <i>u</i> than to vertex <i>v</i> and the number of edges that are closer to vertex <i>v</i> than to vertex <i>u</i>, respectively. In this paper, we determine the upper bound of the edge Mostar index for all bicyclic graphs and identify the extremal graphs that achieve this bound.