Greater co-operation over energy and security have dominated talks between the presidents of China and Russia and their Central Asian counterparts.
The SCO is becoming increasingly influential
Kazakh President Nursultan Nazarbayev told the Shanghai Co-operation Organisation (SCO) meeting in Bishkek that it should form an energy club.
Guest of honour, Iranian President Mahmoud Ahmadinejad, used the occasion to hit out at US missile defence plans.
The SCO is increasingly seen by some as a way to stem Western influence.
Spanning a strategically important region rich in oil and gas reserves, it is gradually gaining clout and influence, correspondents say.
Mr Nazarbayev said the region's Soviet-era network of gas and oil pipelines could form the basis for an Asian energy market - adding that Kazakhstan had already drawn up a draft strategy for an SCO energy club.
SCO members are undertaking joint military exercises in Russia
"We think that a mechanism of meetings of energy ministers from the SCO member and observer states should function in the context of the idea of an energy club," he told the summit.
"This, in our view, might become one of the main elements of an Asian energy strategy."
He also spoke of the importance of increased co-operation between the SCO and the European Union, particularly over a trans-continental transport corridor "which could be a new manifestation of the traditions of the Great Silk Road".
As well as energy, drug trafficking and political instability in Afghanistan was also discussed at the one-day summit.
The Shanghai Co-operation Organisation, officially formed six years ago, draws together China and Russia and the four much weaker Central Asian states between them - Kazakhstan, Uzbekistan, Tajikistan and Kyrgyzstan.
Most meetings take place behind closed doors, and so far none of the public statements have gone beyond general praise of friendship and deepening of ties.
But these annual summits are becoming increasingly influential, and the alliance is turning into a prestigious regional club with global ambitions, according to Natalia Antelava, the BBC correspondent in Bishkek, Kyrgyzstan.
The main message of this summit is clearly that "the world is bigger than the West", our correspondent says.
This year the summit was attended by the leaders of Iran, Afghanistan, Turkmenistan and Mongolia, as well as senior officials from India and Pakistan.
Iran, in particular, is interested in obtaining full membership status.
Mr Ahmadinejad's visit is adding to the suspicion with which the US and Europe have always viewed the organisation, our correspondent says.
The Iranian leader took the opportunity to tell the summit that US plans for a missile defence shield "concern most of the continent, both Asia and the SCO members".
After the summit, all six SCO leaders were due to travel to Russia where more than 6,000 troops from all member states are holding joint military exercises.
This is proof the SCO is taking its growing role very seriously indeed, our correspondent adds.