St Andrew's Cathedral, Sydney is the cathedral church of the Anglican Diocese of Sydney. It is the seat of the Anglican Archbishop of Sydney and Metropolitan.
Located in central Sydney, it is one of the city's finest examples of Gothic Revival architecture. Designed by Edmund Blacket it was consecrated in 1868, making it the oldest cathedral in Australia.

The early Governor of New South Wales, Lachlan Macquarie, foresaw that Sydney would grow into a large city requiring a large cathedral and planned a church 200 feet square with his architect Francis Greenway, who had been transported to Sydney for forgery. Only a few foundations were laid before the plan was abandoned and Macquarie was severely criticised for planning beyond the colony's means.

Bishop William Broughton, had a new foundation stone laid in 1837 with plans, prepared by the architect James Hume of much more modest proportions. Only one notable section was completed, the façade of the south transept. However, the foundations were laid and some of the walls were constructed up to a height of about 15 feet.

In 1842 Edmund Thomas Blacket presented himself to the Bishop with a letter from the Archbishop of Canterbury recommending his talent as an architect and having equal facility in both the Classical and the Gothic style. He was eventually to become known as the 'Wren of Sydney', having designed two universities, three cathedrals and fifty or more parish churches as well as banks, offices, bridges, mansions and countless shops, cottages and terraced houses. Blacket became the official Colonial Architect 1849-1854.

Blacket was an inventive and stylish Gothic Revival architect and tackled the problem of how to make a truly splendid and imposing cathedral on foundations which were only the size of a large English parish church.
He succeeded in creating a building which, despite its small size, is nevertheless imposing and of harmonious proportions.

Bishop Broughton did not live to consecrate St Andrew's. He died while on a trip to England in 1853 and is buried at Canterbury Cathedral. The second Bishop of Sydney, Frederick Barker, consecrated the completed building on St Andrew's Day, November 30th, 1868.

Between 1999 and 2000 major conservation and restoration work was undertaken to restore the original internal layout, whereby the sanctuary was relocated at the Cathedral's Eastern end. This was achieved under the Very Reverend Boak Jobbins.

In 1866 an organ by the famous English organ builders William Hill and Sons was installed with a case to Edmund Blacket's design and richly decorated organ pipes. It was joined in 1932 by an instrument by John Whitely which was placed opposite in the North transept. In the 1950s the instruments were amalgamated to be played from a single console, thus constituting the largest church organ in Australia.

There are regular Friday afternoon recitals involving Australian and International organists commencing at 1.10 pm (usually for 30 or 40 minutes). These recitals have now been going for more than 40 years.

In 1885 St Andrew's Cathedral School was founded by the third Bishop of Sydney, Bishop Barry. For many years the enrolment stood at 46 boys. The school began to expand in 1941 and in the latter part of the 20th century enrolment stood at 700 and catered for boys from Years 3 to 12. In 1999 girls were admitted to senior years and in 2008 St Andrew's Cathedral School became fully co-educational from Kindergarten.

St Andrew's has a peal of 10 bells cast by John Taylor and Co. of Loughborough in England and installed in 1965 to the memory of Ernest Samuel Trigg. The tenor weighs 29 ¼ cwt and the lightest 6½ cwt. The bells have since been augmented with three more. They are rung each Sunday at 9.45am.